diff --git a/app/src/main/java/org/solovyev/android/calculator/Display.java b/app/src/main/java/org/solovyev/android/calculator/Display.java
index 809632c8..a58ec550 100644
--- a/app/src/main/java/org/solovyev/android/calculator/Display.java
+++ b/app/src/main/java/org/solovyev/android/calculator/Display.java
@@ -37,13 +37,13 @@ import org.solovyev.android.calculator.calculations.ConversionFailedEvent;
 import org.solovyev.android.calculator.calculations.ConversionFinishedEvent;
 import org.solovyev.android.calculator.errors.FixableErrorsActivity;
 
-import dagger.Lazy;
-
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 import javax.inject.Singleton;
 
+import dagger.Lazy;
+
 @Singleton
 public class Display {
 
@@ -80,8 +80,7 @@ public class Display {
             return;
         }
         clipboard.get().setText(state.text);
-        notifier.get().showMessage(
-                CalculatorMessage.newInfoMessage(CalculatorMessages.result_copied));
+        notifier.get().showMessage(R.string.cpp_text_copied);
     }
 
     @Subscribe
diff --git a/app/src/main/java/org/solovyev/android/calculator/FragmentTab.java b/app/src/main/java/org/solovyev/android/calculator/FragmentTab.java
index d7bc887e..f6dc38a0 100644
--- a/app/src/main/java/org/solovyev/android/calculator/FragmentTab.java
+++ b/app/src/main/java/org/solovyev/android/calculator/FragmentTab.java
@@ -38,7 +38,7 @@ public enum FragmentTab {
 
     history(RecentHistoryFragment.class, R.string.cpp_history_tab_recent),
     saved_history(SavedHistoryFragment.class, R.string.cpp_history_tab_saved),
-    variables(VariablesFragment.class, R.string.c_vars),
+    variables(VariablesFragment.class, R.string.c_vars_and_constants),
     functions(FunctionsFragment.class, R.string.c_functions),
     operators(OperatorsFragment.class, R.string.c_operators),
     about(AboutFragment.class, R.string.cpp_about),
diff --git a/app/src/main/java/org/solovyev/android/calculator/converter/ConverterFragment.java b/app/src/main/java/org/solovyev/android/calculator/converter/ConverterFragment.java
index 275f5173..c97f1a7d 100644
--- a/app/src/main/java/org/solovyev/android/calculator/converter/ConverterFragment.java
+++ b/app/src/main/java/org/solovyev/android/calculator/converter/ConverterFragment.java
@@ -389,7 +389,7 @@ public class ConverterFragment extends BaseDialogFragment
                     break;
                 case DialogInterface.BUTTON_NEUTRAL:
                     clipboard.setText(text);
-                    Toast.makeText(getActivity(), getString(R.string.c_result_copied),
+                    Toast.makeText(getActivity(), getString(R.string.cpp_text_copied),
                             Toast.LENGTH_SHORT).show();
                     break;
             }
diff --git a/app/src/main/java/org/solovyev/android/calculator/variables/EditVariableFragment.java b/app/src/main/java/org/solovyev/android/calculator/variables/EditVariableFragment.java
index 77b3176c..b356784b 100644
--- a/app/src/main/java/org/solovyev/android/calculator/variables/EditVariableFragment.java
+++ b/app/src/main/java/org/solovyev/android/calculator/variables/EditVariableFragment.java
@@ -44,12 +44,19 @@ import android.view.inputmethod.InputMethodManager;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.PopupWindow;
-import butterknife.Bind;
-import butterknife.ButterKnife;
-import dagger.Lazy;
-import jscl.math.function.IConstant;
+
 import org.solovyev.android.Check;
-import org.solovyev.android.calculator.*;
+import org.solovyev.android.calculator.App;
+import org.solovyev.android.calculator.AppComponent;
+import org.solovyev.android.calculator.BaseDialogFragment;
+import org.solovyev.android.calculator.Calculator;
+import org.solovyev.android.calculator.Engine;
+import org.solovyev.android.calculator.Keyboard;
+import org.solovyev.android.calculator.PreparedExpression;
+import org.solovyev.android.calculator.R;
+import org.solovyev.android.calculator.RemovalConfirmationDialog;
+import org.solovyev.android.calculator.ToJsclTextProcessor;
+import org.solovyev.android.calculator.VariablesRegistry;
 import org.solovyev.android.calculator.functions.FunctionsRegistry;
 import org.solovyev.android.calculator.keyboard.FloatingKeyboard;
 import org.solovyev.android.calculator.keyboard.FloatingKeyboardWindow;
@@ -58,11 +65,17 @@ import org.solovyev.android.calculator.view.EditTextCompat;
 import org.solovyev.android.text.method.NumberInputFilter;
 import org.solovyev.common.text.Strings;
 
+import java.util.Arrays;
+import java.util.List;
+
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.inject.Inject;
-import java.util.Arrays;
-import java.util.List;
+
+import butterknife.Bind;
+import butterknife.ButterKnife;
+import dagger.Lazy;
+import jscl.math.function.IConstant;
 
 import static org.solovyev.android.calculator.variables.CppVariable.NO_ID;
 
@@ -253,7 +266,7 @@ public class EditVariableFragment extends BaseDialogFragment implements View.OnF
     private boolean validateName() {
         final String name = nameView.getText().toString();
         if (!Engine.isValidName(name)) {
-            setError(nameLabel, getString(R.string.c_name_is_not_valid));
+            setError(nameLabel, getString(R.string.cpp_name_contains_invalid_characters));
             return false;
         }
         for (int i = 0; i < name.length(); i++) {
diff --git a/app/src/main/res/layout/cpp_app_button_clear.xml b/app/src/main/res/layout/cpp_app_button_clear.xml
index 3c3ee5cb..4012f5a1 100644
--- a/app/src/main/res/layout/cpp_app_button_clear.xml
+++ b/app/src/main/res/layout/cpp_app_button_clear.xml
@@ -27,6 +27,6 @@
     style="?attr/cpp_button_style_control_highlighted"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:a="http://schemas.android.com/apk/res/android"
-    a:text="@string/c_clear"
+    a:text="@string/cpp_kb_clear"
     app:directionTextUp="@string/cpp_kb_memory_clear"
     a:textStyle="bold"/>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_simple_button_clear.xml b/app/src/main/res/layout/cpp_simple_button_clear.xml
index 1b7d25d7..5f86874e 100644
--- a/app/src/main/res/layout/cpp_simple_button_clear.xml
+++ b/app/src/main/res/layout/cpp_simple_button_clear.xml
@@ -26,5 +26,5 @@
     xmlns:a="http://schemas.android.com/apk/res/android"
     a:id="@id/cpp_button_clear"
     style="@style/CppKeyboardButton.Metro.Simple.Control"
-    a:text="@string/c_clear"
+    a:text="@string/cpp_kb_clear"
     a:textStyle="bold" />
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_simple_button_clear_material.xml b/app/src/main/res/layout/cpp_simple_button_clear_material.xml
index 51c66f70..5ea2d0f1 100644
--- a/app/src/main/res/layout/cpp_simple_button_clear_material.xml
+++ b/app/src/main/res/layout/cpp_simple_button_clear_material.xml
@@ -26,5 +26,5 @@
     xmlns:a="http://schemas.android.com/apk/res/android"
     a:id="@id/cpp_button_clear"
     style="@style/CppKeyboardButton.Material.Simple.Control.Highlighted"
-    a:text="@string/c_clear"
+    a:text="@string/cpp_kb_clear"
     a:textStyle="bold" />
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_simple_button_clear_material_light.xml b/app/src/main/res/layout/cpp_simple_button_clear_material_light.xml
index e7aad087..f96a5ac4 100644
--- a/app/src/main/res/layout/cpp_simple_button_clear_material_light.xml
+++ b/app/src/main/res/layout/cpp_simple_button_clear_material_light.xml
@@ -26,5 +26,5 @@
     xmlns:a="http://schemas.android.com/apk/res/android"
     a:id="@id/cpp_button_clear"
     style="@style/CppKeyboardButton.Material.Light.Simple.Control.Highlighted"
-    a:text="@string/c_clear"
+    a:text="@string/cpp_kb_clear"
     a:textStyle="bold" />
\ No newline at end of file
diff --git a/app/src/main/res/layout/fragment_function_edit_base_controls.xml b/app/src/main/res/layout/fragment_function_edit_base_controls.xml
index 7dac879a..c7cb3c7a 100644
--- a/app/src/main/res/layout/fragment_function_edit_base_controls.xml
+++ b/app/src/main/res/layout/fragment_function_edit_base_controls.xml
@@ -33,7 +33,7 @@
             a:id="@+id/function_name"
             a:layout_width="match_parent"
             a:layout_height="wrap_content"
-            a:hint="@string/c_function_name"
+            a:hint="@string/cpp_name"
             a:inputType="text" />
     </android.support.design.widget.TextInputLayout>
 
diff --git a/app/src/main/res/layout/fragment_variable_edit.xml b/app/src/main/res/layout/fragment_variable_edit.xml
index 26b9ce45..a366f458 100644
--- a/app/src/main/res/layout/fragment_variable_edit.xml
+++ b/app/src/main/res/layout/fragment_variable_edit.xml
@@ -46,7 +46,7 @@
                     a:id="@+id/variable_name"
                     a:layout_width="match_parent"
                     a:layout_height="wrap_content"
-                    a:hint="@string/c_var_name"
+                    a:hint="@string/cpp_name"
                     a:inputType="text" />
 
             </android.support.design.widget.TextInputLayout>
diff --git a/app/src/main/res/values-ar/strings.xml b/app/src/main/res/values-ar/strings.xml
index 6b004f62..4a2676fd 100644
--- a/app/src/main/res/values-ar/strings.xml
+++ b/app/src/main/res/values-ar/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">الآلة الحاسبة++</string>
     <string name="c_app_name_on_screen">الآلة الحاسبة++ (نمط النافذة)</string>
-    <string name="c_result_copied">تم نسخ النتيجة الى الحافظة!</string>
     <string name="c_vars_and_constants">المتغيرات والثوابت</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">المتغيرات</string>
     <string name="c_plot">رسم الدالّة</string>
     <string name="cpp_precision">دقة النتيجة</string>
     <string name="c_save">حفظ</string>
     <string name="removal_confirmation">تأكيد الإزالة</string>
     <string name="c_var_removal_confirmation_question">هل تريد حقاً حذف المتغير \'%s\'؟</string>
-    <string name="c_var_name">الاسم</string>
     <string name="c_var_value">القيمة</string>
     <string name="c_var_description">الوصف</string>
     <string name="c_var_create_var">إنشاء متغير</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">يجب أن تكون القيمة رقماً أو تترك فارغة: إذا كان لديك عوامل متغيرة - قم بإنشاء دالة بدلاً من ذلك!</string>
     <string name="c_var_name_clashes">اسم المتغير يتشابك مع اسم الدالة!</string>
     <string name="c_var_already_exists">متغير يحمل نفس الاسم موجود مسبقاً!</string>
-    <string name="c_name_is_not_valid">اسم الثابت غير صحيح: الاسم يجب أن يبدأ بحرف, ويمكن أن يحتوي على أحرف وأرقام و إشارة _ .</string>
     <string name="c_history">السجل</string>
     <string name="c_char_is_not_accepted">المحرف \'%s\' غير مقبول في اسم المتغير!</string>
     <string name="cpp_deg">درجات</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">تحويل الى عشري</string>
     <string name="other">الأخرى</string>
     <string name="derivatives">المشتقات/التكاملات</string>
-    <string name="c_function_name">الاسم</string>
     <string name="function_create_function">قم بإنشاء دالّة</string>
     <string name="function_edit_function">تعديل الدالّة</string>
     <string name="function_already_exists">هناك دالّة بنفس الاسم موجود مسبقاً!</string>
diff --git a/app/src/main/res/values-cs/strings.xml b/app/src/main/res/values-cs/strings.xml
index abae962a..f591c910 100644
--- a/app/src/main/res/values-cs/strings.xml
+++ b/app/src/main/res/values-cs/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Kalkulačka ++ (Režim okna)</string>
-    <string name="c_result_copied">Výsledek byl zkopírován do schránky!</string>
     <string name="c_vars_and_constants">Proměnné a Konstanty</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">proměnné</string>
     <string name="c_plot">Vykreslit graf</string>
     <string name="cpp_precision">Přesnost výsledku</string>
     <string name="c_save">Uložit</string>
     <string name="removal_confirmation">Potvrzení odebrání</string>
     <string name="c_var_removal_confirmation_question">Opravdu chcete odstranit proměnnou \'%s\'?</string>
-    <string name="c_var_name">Jméno</string>
     <string name="c_var_value">Hodnota</string>
     <string name="c_var_description">Popis</string>
     <string name="c_var_create_var">Vytvořit proměnnou</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">Hodnota musí být číslo nebo zůstat prázdná: Pokud máte parametry - vytvořte místo toho funkci!</string>
     <string name="c_var_name_clashes">Název proměnné se rovná názvu funkce!</string>
     <string name="c_var_already_exists">Proměnná se stejným názvem již existuje!</string>
-    <string name="c_name_is_not_valid">Název konstanty není platný: jméno musí začínat písmenem, může obsahovat písmena, číslice a podtržítka.</string>
     <string name="c_history">Historie</string>
     <string name="c_char_is_not_accepted">Znak \'%s\' není povolen v názvu proměnné!</string>
     <string name="cpp_deg">Stupňů</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Převést do dec</string>
     <string name="other">Ostatní</string>
     <string name="derivatives">Derivace/Integrály</string>
-    <string name="c_function_name">Jméno</string>
     <string name="function_create_function">Vytvořit funkci</string>
     <string name="function_edit_function">Upravit funkci</string>
     <string name="function_already_exists">Funkce se stejným názvem již existuje!</string>
diff --git a/app/src/main/res/values-de/strings.xml b/app/src/main/res/values-de/strings.xml
index ab6dd2f4..d09b1fad 100644
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++ (Fenstermodus)</string>
-    <string name="c_result_copied">Ergebnis wurde in die Zwischenablage kopiert!</string>
     <string name="c_vars_and_constants">Variablen und Konstanten</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">Variablen</string>
     <string name="c_plot">Graph zeichnen</string>
     <string name="cpp_precision">Genauigkeit des Ergebnisses</string>
     <string name="c_save">Speichern</string>
     <string name="removal_confirmation">Löschbestätigung</string>
     <string name="c_var_removal_confirmation_question">Möchten Sie die Variable \'%s\' wirklich löschen?</string>
-    <string name="c_var_name">Name</string>
     <string name="c_var_value">Wert</string>
     <string name="c_var_description">Beschreibung</string>
     <string name="c_var_create_var">Erstelle Variable</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">Wert muss entweder eine Zahl oder leer sein. Wenn Sie Parameter benötigen, erstellen Sie stattdessen eine Funktion!</string>
     <string name="c_var_name_clashes">Variablenname überschneidet sich mit Funktionsnamen!</string>
     <string name="c_var_already_exists">Variable mit gleichen Namen existiert bereits!</string>
-    <string name="c_name_is_not_valid">Name der Konstante ist ungültig: Name muss mit einem Buchstaben beginnen und darf nur Buchstaben, Ziffern und Unterstriche enthalten.</string>
     <string name="c_history">Verlauf</string>
     <string name="c_char_is_not_accepted">Zeichen \'%s\' kann in den Variablennamen nicht akzeptiert werden!</string>
     <string name="cpp_deg">Grad</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Umrechnen in Dez</string>
     <string name="other">Andere</string>
     <string name="derivatives">Ableitungen/Integrale</string>
-    <string name="c_function_name">Name</string>
     <string name="function_create_function">Funktion erstellen</string>
     <string name="function_edit_function">Funktion bearbeiten</string>
     <string name="function_already_exists">Funktion mit demselben Namen existiert bereits!</string>
diff --git a/app/src/main/res/values-es/strings.xml b/app/src/main/res/values-es/strings.xml
index ab6c562a..72a48d09 100644
--- a/app/src/main/res/values-es/strings.xml
+++ b/app/src/main/res/values-es/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculadora++</string>
     <string name="c_app_name_on_screen">Calculadora++ (Modo ventana)</string>
-    <string name="c_result_copied">¡El resultado se ha copiado en el portapapeles!</string>
     <string name="c_vars_and_constants">Variables y Constantes</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">variables</string>
     <string name="c_plot">Trazar gráfico</string>
     <string name="cpp_precision">Precisión del resultado</string>
     <string name="c_save">Grabar</string>
     <string name="removal_confirmation">Confirmación de Borrado</string>
     <string name="c_var_removal_confirmation_question">¿Realmente desea borrar la variable \'%s\'?</string>
-    <string name="c_var_name">Nombre</string>
     <string name="c_var_value">Valor</string>
     <string name="c_var_description">Descripción</string>
     <string name="c_var_create_var">Crear variable</string>
@@ -19,8 +15,6 @@
     <string name="c_value_is_not_a_number">¡El valor debe ser numérico o estar vacío: Si tienes parámetros - crea un a función en su lugar!</string>
     <string name="c_var_name_clashes">La variable name entra en conflicto con la función name!</string>
     <string name="c_var_already_exists">¡Ya existe una variable con el mismo nombre!</string>
-  <string name="c_name_is_not_valid">El nombre de la constante no es válido: el nombre debe comenzar con una letra, y puede contener letras, dígitos y líneas.
-	</string>
     <string name="c_history">Historial</string>
     <string name="c_char_is_not_accepted">El carácter \'%s\' no es aceptado como variable!</string>
     <string name="cpp_deg">Grados</string>
@@ -58,7 +52,6 @@
     <string name="convert_to_dec">Convertir a numero decimal</string>
     <string name="other">Otro</string>
     <string name="derivatives">Derivadas/Integrales</string>
-    <string name="c_function_name">Nombre</string>
     <string name="function_create_function">Crear función</string>
     <string name="function_edit_function">Editar función</string>
     <string name="function_already_exists">¡Ya existe una función con el mismo nombre!</string>
diff --git a/app/src/main/res/values-fi/strings.xml b/app/src/main/res/values-fi/strings.xml
index 456d3daa..42757f2c 100644
--- a/app/src/main/res/values-fi/strings.xml
+++ b/app/src/main/res/values-fi/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Laskin++</string>
     <string name="c_app_name_on_screen">Laskin++ (ikkuna-tilassa)</string>
-    <string name="c_result_copied">Tulos on kopioitu Leikepöydälle!</string>
     <string name="c_vars_and_constants">Muuttujien ja vakioiden</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">Vars</string>
     <string name="c_plot">Kaavion tulostamisessa</string>
     <string name="cpp_precision">Tarkka tulos</string>
     <string name="c_save">Tallenna</string>
     <string name="removal_confirmation">Poistamisvahvistus</string>
     <string name="c_var_removal_confirmation_question">Haluatko todella poistaa %s muuttujan?</string>
-    <string name="c_var_name">Nimi</string>
     <string name="c_var_value">Arvo</string>
     <string name="c_var_description">Kuvaus</string>
     <string name="c_var_create_var">Muuttuja luodaan</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">Arvon on oltava joko numero tai jätetty tyhjäksi: Jos sinulla on parametrit - funktion luominen sen sijaan!</string>
     <string name="c_var_name_clashes">Muuttujan nimi törmää funktionimi!</string>
     <string name="c_var_already_exists">Muuttuja, jolla on sama nimi on jo olemassa!</string>
-    <string name="c_name_is_not_valid">Vakion nimi ei kelpaa: nimen on alettava kirjaimella, voi sisältää kirjaimia, numeroita ja alaviivoja.  </string>
     <string name="c_history">Historia</string>
     <string name="c_char_is_not_accepted">Merkki \'%s\' ei ole hyväksytty muuttujan nimi!</string>
     <string name="cpp_deg">Astetta</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Muuntaa dec</string>
     <string name="other">Muut</string>
     <string name="derivatives">Johdannaisten ja integraalit</string>
-    <string name="c_function_name">Nimi</string>
     <string name="function_create_function">Funktion luominen</string>
     <string name="function_edit_function">Muokkaa funktiota</string>
     <string name="function_already_exists">Saman niminen toiminto on jo olemassa!</string>
diff --git a/app/src/main/res/values-fr/strings.xml b/app/src/main/res/values-fr/strings.xml
index 1f6352da..25411455 100644
--- a/app/src/main/res/values-fr/strings.xml
+++ b/app/src/main/res/values-fr/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++ (mode fenêtre)</string>
-    <string name="c_result_copied">Le résultat a été copié dans le presse-papiers !</string>
     <string name="c_vars_and_constants">Variables et constantes</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">Variables</string>
     <string name="c_plot">Tracer le graphe</string>
     <string name="cpp_precision">Précision du résultat</string>
     <string name="c_save">Enregistrer</string>
     <string name="removal_confirmation">Confirmation de suppression</string>
     <string name="c_var_removal_confirmation_question">Voulez-vous vraiment supprimer la variable « %s » ?</string>
-    <string name="c_var_name">Nom</string>
     <string name="c_var_value">Valeur</string>
     <string name="c_var_description">Description</string>
     <string name="c_var_create_var">Créer une variable</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">La valeur doit être un nombre ou être laissée vide. Si vous avez des paramètres, créez plutôt une fonction !</string>
     <string name="c_var_name_clashes">Nom de variable en conflit avec le nom d\'une fonction !</string>
     <string name="c_var_already_exists">Une variable portant le même nom existe déjà !</string>
-    <string name="c_name_is_not_valid">Le nom de la constante n\'est pas valide : le nom doit commencer par une lettre, peut contenir des lettres, chiffres et trait de soulignement.  </string>
     <string name="c_history">Historique</string>
     <string name="c_char_is_not_accepted">Le caractère \'%s\' n\'est pas accepté dans le nom de la variable !</string>
     <string name="cpp_deg">Degrés</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Convertir en déc</string>
     <string name="other">Autre</string>
     <string name="derivatives">Dérivation/Intégration</string>
-    <string name="c_function_name">Nom</string>
     <string name="function_create_function">Créer une fonction</string>
     <string name="function_edit_function">Modifier la fonction</string>
     <string name="function_already_exists">Une fonction portant le même nom existe déjà !</string>
diff --git a/app/src/main/res/values-it/strings.xml b/app/src/main/res/values-it/strings.xml
index 582d0b8f..3bd8cab5 100644
--- a/app/src/main/res/values-it/strings.xml
+++ b/app/src/main/res/values-it/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calcolatrice++</string>
     <string name="c_app_name_on_screen">Calcolatrice++ (Modalità finestra)</string>
-    <string name="c_result_copied">Il risultato è stato copiato negli appunti!</string>
     <string name="c_vars_and_constants">Variabili e costanti</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">variabili</string>
     <string name="c_plot">Plot grafico</string>
     <string name="cpp_precision">Precisione del risultato</string>
     <string name="c_save">Salva</string>
     <string name="removal_confirmation">Conferma rimozione</string>
     <string name="c_var_removal_confirmation_question">Vuoi davvero cancellare la variabile \'%s\'?</string>
-    <string name="c_var_name">Nome</string>
     <string name="c_var_value">Valore</string>
     <string name="c_var_description">Descrizione</string>
     <string name="c_var_create_var">Crea variabile</string>
@@ -19,9 +15,6 @@
     <string name="c_value_is_not_a_number">Il valore deve essere un numero o lasciato vuoto: se disponi di parametri, crea invece una funzione!</string>
     <string name="c_var_name_clashes">Il nome della variabile entra in conflitto col nome della funzione!</string>
     <string name="c_var_already_exists">Esiste già una variabile con lo stesso nome!</string>
-  <string name="c_name_is_not_valid">Il nome della costante non è valido: il nome deve iniziare con una lettera, può
-		contenere lettere, cifre e underscore.
-	</string>
     <string name="c_history">Cronologia</string>
     <string name="c_char_is_not_accepted">Il carattere \'%s\' non è accettato come nome di variabile!</string>
     <string name="cpp_deg">Gradi</string>
@@ -59,7 +52,6 @@
     <string name="convert_to_dec">Converti in decimale (dec)</string>
     <string name="other">Altri</string>
     <string name="derivatives">Derivate/Integrali</string>
-    <string name="c_function_name">Nome</string>
     <string name="function_create_function">Crea la funzione</string>
     <string name="function_edit_function">Modifica funzione</string>
     <string name="function_already_exists">Funzione con lo stesso nome esiste già!</string>
diff --git a/app/src/main/res/values-ja/strings.xml b/app/src/main/res/values-ja/strings.xml
index be73048b..ae9b790d 100644
--- a/app/src/main/res/values-ja/strings.xml
+++ b/app/src/main/res/values-ja/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++ (ウィンドウモード)</string>
-    <string name="c_result_copied">計算結果をクリップボードにコピーしました！</string>
     <string name="c_vars_and_constants">変数と定数</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">変数</string>
     <string name="c_plot">グラフをプロット</string>
     <string name="cpp_precision">計算結果の有効桁数</string>
     <string name="c_save">保存</string>
     <string name="removal_confirmation">削除の確認</string>
     <string name="c_var_removal_confirmation_question">本当に変数 \'%s\' を削除しますか？</string>
-    <string name="c_var_name">名前</string>
     <string name="c_var_value">値</string>
     <string name="c_var_description">説明</string>
     <string name="c_var_create_var">変数を作成</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">値は数値、もしくは空のままである必要があります。パラメータを入力したい場合は、代わりに関数を作成してください。</string>
     <string name="c_var_name_clashes">変数名が関数名とかぶっています</string>
     <string name="c_var_already_exists">同じ名前の変数がすでに存在しています!</string>
-    <string name="c_name_is_not_valid">定数の名前が正しくありません: 名前は文字で始める必要があり、文字、数字、アンダースコアを含めることができます。</string>
     <string name="c_history">履歴</string>
     <string name="c_char_is_not_accepted">文字\'%s\'は変数名として利用できません!</string>
     <string name="cpp_deg">度</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">10進数に変換</string>
     <string name="other">その他</string>
     <string name="derivatives">微分・積分</string>
-    <string name="c_function_name">名前</string>
     <string name="function_create_function">関数の作成</string>
     <string name="function_edit_function">関数の編集</string>
     <string name="function_already_exists">同じ名前を持つ関数が既に存在します!</string>
diff --git a/app/src/main/res/values-nl/strings.xml b/app/src/main/res/values-nl/strings.xml
index df4c5101..2b5f3032 100644
--- a/app/src/main/res/values-nl/strings.xml
+++ b/app/src/main/res/values-nl/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++ (Window mode)</string>
-    <string name="c_result_copied">Resultaat is gekopieerd naar het klembord!</string>
     <string name="c_vars_and_constants">Variabelen en constanten</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">vars</string>
     <string name="c_plot">Uitzetten van grafiek</string>
     <string name="cpp_precision">Nauwkeurigheid van resultaat</string>
     <string name="c_save">Opslaan</string>
     <string name="removal_confirmation">Verwijderen bevestigen</string>
     <string name="c_var_removal_confirmation_question">Wilt u echt \'%s\' variabele verwijderen?</string>
-    <string name="c_var_name">Naam</string>
     <string name="c_var_value">Waarde</string>
     <string name="c_var_description">Beschrijving</string>
     <string name="c_var_create_var">Variabele maken</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">Waarde moet een getal zijn ofwel leeg gelaten worden: als u parameters hebt - maak dan een functie aan!</string>
     <string name="c_var_name_clashes">Naam van de variabele is in conflict met de naam van de functie!</string>
     <string name="c_var_already_exists">Variabele met dezelfde naam bestaat al!</string>
-    <string name="c_name_is_not_valid">Naam van de constante is niet geldig: naam moet beginnen met een letter, kan letters, cijfers en underscores bevatten. </string>
     <string name="c_history">Geschiedenis</string>
     <string name="c_char_is_not_accepted">Teken \'%s\' is niet geaccepteerd in naam van de variabele!</string>
     <string name="cpp_deg">Graden</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Converteren naar dec</string>
     <string name="other">Andere</string>
     <string name="derivatives">Afgeleiden/integralen</string>
-    <string name="c_function_name">Naam</string>
     <string name="function_create_function">Functie maken</string>
     <string name="function_edit_function">Functie bewerken</string>
     <string name="function_already_exists">Functienaam is al gebruikt!</string>
diff --git a/app/src/main/res/values-pl/strings.xml b/app/src/main/res/values-pl/strings.xml
index 7a90c09e..4be677e4 100644
--- a/app/src/main/res/values-pl/strings.xml
+++ b/app/src/main/res/values-pl/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++ (tryb okna)</string>
-    <string name="c_result_copied">Wynik został skopiowany do schowka!</string>
     <string name="c_vars_and_constants">Zmienne i stałe</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">zmienne</string>
     <string name="c_plot">Stwórz wykres</string>
     <string name="cpp_precision">Dokładność wyniku</string>
     <string name="c_save">Zapisz</string>
     <string name="removal_confirmation">Potwierdzenie usunięcia</string>
     <string name="c_var_removal_confirmation_question">Czy na pewno chcesz usunąć zmienną \'%s\'?</string>
-    <string name="c_var_name">Nazwa</string>
     <string name="c_var_value">Wartość</string>
     <string name="c_var_description">Opis</string>
     <string name="c_var_create_var">Stwórz zmienną</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">Wartość musi być liczbą lub być pusta: jeśli masz parametry - stwórz funkcję zamiast tego!</string>
     <string name="c_var_name_clashes">Nazwa zmiennej pokrywa się z nazwą funkcji!</string>
     <string name="c_var_already_exists">Zmienna o tej samej nazwie już istnieje!</string>
-    <string name="c_name_is_not_valid">Nazwa stałej jest nieprawidłowa: nazwa musi zaczynać się od litery, może zawierać litery, cyfry lub znak podkreślenia.</string>
     <string name="c_history">Historia</string>
     <string name="c_char_is_not_accepted">Znak \'%s\' nie może być użyty w nazwie zmiennej!</string>
     <string name="cpp_deg">Stopnie</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Zamień na dec</string>
     <string name="other">Inne</string>
     <string name="derivatives">Pochodne/Całki</string>
-    <string name="c_function_name">Nazwa</string>
     <string name="function_create_function">Stwórz funkcję</string>
     <string name="function_edit_function">Edytuj funkcję</string>
     <string name="function_already_exists">Funkcja o takiej samej nazwie już istnieje!</string>
diff --git a/app/src/main/res/values-pt-rBR/strings.xml b/app/src/main/res/values-pt-rBR/strings.xml
index b193bc49..2f8022d2 100644
--- a/app/src/main/res/values-pt-rBR/strings.xml
+++ b/app/src/main/res/values-pt-rBR/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++ (Modo Janela)</string>
-    <string name="c_result_copied">Resultado foi copiado para a área de transferência!</string>
     <string name="c_vars_and_constants">Variáveis e constantes</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">vars</string>
     <string name="c_plot">Desenhar o gráfico</string>
     <string name="cpp_precision">Precisão do resultado</string>
     <string name="c_save">Salvar</string>
     <string name="removal_confirmation">Confirmação de remoção</string>
     <string name="c_var_removal_confirmation_question">Você quer realmente excluir a variável \'%s\'?</string>
-    <string name="c_var_name">Nome</string>
     <string name="c_var_value">Valor</string>
     <string name="c_var_description">Descrição</string>
     <string name="c_var_create_var">Criar a variável</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">O valor à esquerda deve ser um número ou ficar vazio: se você tiver parâmetros - crie uma função em vez disso!</string>
     <string name="c_var_name_clashes">Conflito: existe uma função com mesmo nome da variável!</string>
     <string name="c_var_already_exists">Já existe uma variável com mesmo nome!</string>
-    <string name="c_name_is_not_valid">O nome da constante não é válido: o nome deve iniciar com uma letra, pode conter letras, dígitos e sublinhado.  </string>
     <string name="c_history">Histórico</string>
     <string name="c_char_is_not_accepted">Caractere \'%s\' não é aceito em nome de variável!</string>
     <string name="cpp_deg">Graus</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Converter para decimal</string>
     <string name="other">Outros</string>
     <string name="derivatives">Derivadas/Integrais</string>
-    <string name="c_function_name">Nome</string>
     <string name="function_create_function">Criar função</string>
     <string name="function_edit_function">Editar função</string>
     <string name="function_already_exists">Já existe uma função com o mesmo nome!</string>
diff --git a/app/src/main/res/values-pt-rPT/strings.xml b/app/src/main/res/values-pt-rPT/strings.xml
index 3eb06a38..68f99055 100644
--- a/app/src/main/res/values-pt-rPT/strings.xml
+++ b/app/src/main/res/values-pt-rPT/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++ (Modo de Janela)</string>
-    <string name="c_result_copied">O resultado foi copiado para a área de transferência!</string>
     <string name="c_vars_and_constants">Variáveis e Constantes</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">variáveis</string>
     <string name="c_plot">Desenhar gráfico</string>
     <string name="cpp_precision">Precisão do resultado</string>
     <string name="c_save">Guardar</string>
     <string name="removal_confirmation">Confirmação de remoção</string>
     <string name="c_var_removal_confirmation_question">Deseja realmente apagar a variável \'%s\'?</string>
-    <string name="c_var_name">Nome</string>
     <string name="c_var_value">Valor</string>
     <string name="c_var_description">Descrição</string>
     <string name="c_var_create_var">Criar variável</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">O valor deve ser um número ou deve ser deixado vazio: se tiver parâmetros - crie em vez disso uma função!</string>
     <string name="c_var_name_clashes">Nome da variável colide com o nome da função!</string>
     <string name="c_var_already_exists">Já existe uma variável com o mesmo nome!</string>
-    <string name="c_name_is_not_valid">O nome da constante não é válido: o nome deve começar por uma letra, pode conter letras, dígitos e underscore.</string>
     <string name="c_history">Histórico</string>
     <string name="c_char_is_not_accepted">O caracter \'%s\' não é aceite como nome de variável!</string>
     <string name="cpp_deg">Graus</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Converter para dec</string>
     <string name="other">Outro</string>
     <string name="derivatives">Derivadas/Integrais</string>
-    <string name="c_function_name">Nome</string>
     <string name="function_create_function">Criar função</string>
     <string name="function_edit_function">Editar função</string>
     <string name="function_already_exists">Já existe uma função com o mesmo nome !</string>
diff --git a/app/src/main/res/values-ru/strings.xml b/app/src/main/res/values-ru/strings.xml
index d7c63050..ef2bde72 100644
--- a/app/src/main/res/values-ru/strings.xml
+++ b/app/src/main/res/values-ru/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Калькулятор++</string>
     <string name="c_app_name_on_screen">Калькулятор++ (В отдельном окне)</string>
-    <string name="c_result_copied">Результат был скопирован в буфер обмена!</string>
     <string name="c_vars_and_constants">Переменные и константы</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">переменные</string>
     <string name="c_plot">Построить график</string>
     <string name="cpp_precision">Точность</string>
     <string name="c_save">Сохранить</string>
     <string name="removal_confirmation">Подтверждение удаления</string>
     <string name="c_var_removal_confirmation_question">Вы действительно хотите удалить переменную \'%s\'?</string>
-    <string name="c_var_name">Имя</string>
     <string name="c_var_value">Значение</string>
     <string name="c_var_description">Описание</string>
     <string name="c_var_create_var">Создать переменную</string>
@@ -21,9 +17,6 @@
 	</string>
     <string name="c_var_name_clashes">Имя переменной не может быть зарезервированным системным именем!</string>
     <string name="c_var_already_exists">Переменная с таким именем уже существует!</string>
-  <string name="c_name_is_not_valid">Имя переменной не валидно: имя должно начинаться с буквы, может содержать буквы,
-		цифры и знак подчёркивания.
-	</string>
     <string name="c_history">История</string>
     <string name="c_char_is_not_accepted">Символ \'%s\' не допустим в названии переменной!</string>
     <string name="cpp_deg">Градусы</string>
@@ -62,7 +55,6 @@
     <string name="convert_to_dec">Перевести в dec</string>
     <string name="other">Другие</string>
     <string name="derivatives">Производные/Интегралы</string>
-    <string name="c_function_name">Имя</string>
     <string name="function_create_function">Создать функцию</string>
     <string name="function_edit_function">Редактировать функцию</string>
     <string name="function_already_exists">Функция с таким именем уже существует!</string>
diff --git a/app/src/main/res/values-tr/strings.xml b/app/src/main/res/values-tr/strings.xml
index 350a4ae3..e9719bb4 100644
--- a/app/src/main/res/values-tr/strings.xml
+++ b/app/src/main/res/values-tr/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++ (Pencere modu)</string>
-    <string name="c_result_copied">Sonuç panoya kopyalandı!</string>
     <string name="c_vars_and_constants">Değişkenler ve sabitler</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">Değişkenler</string>
     <string name="c_plot">Grafik Çiz</string>
     <string name="cpp_precision">Sonuç hassasiyeti</string>
     <string name="c_save">Kaydet</string>
     <string name="removal_confirmation">Silme onayı</string>
     <string name="c_var_removal_confirmation_question">%s değişkenini silmek istiyor musunuz?</string>
-    <string name="c_var_name">İsim</string>
     <string name="c_var_value">Değer</string>
     <string name="c_var_description">Açıklama</string>
     <string name="c_var_create_var">Değişken oluştur</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">Atadığınız değer bir sayı olmalı veya değer atamamalısınız. Parametreleriniz varsa fonksiyon oluşturmayı deneyin.</string>
     <string name="c_var_name_clashes">Değişken adı fonksiyon adıyla aynı olamaz! </string>
     <string name="c_var_already_exists">Aynı isimde bir değişken zaten var!</string>
-    <string name="c_name_is_not_valid">Sabitinizin ismi geçerli değil: İsim, harfle başlamalıdır; alt çizgi(_) ve sayı içerebilir. </string>
     <string name="c_history">Geçmiş</string>
     <string name="c_char_is_not_accepted"> \'%s\' karakteri geçerli bir değişken ismi değil!</string>
     <string name="cpp_deg">Derece</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Dec\' e dönüştür</string>
     <string name="other">Diğer</string>
     <string name="derivatives">Türev/Integral</string>
-    <string name="c_function_name">İsim</string>
     <string name="function_create_function">Fonksiyon oluştur</string>
     <string name="function_edit_function">Fonksiyobu düzenle</string>
     <string name="function_already_exists">Aynı isimi bir fonksiyon zaten var!</string>
diff --git a/app/src/main/res/values-uk/strings.xml b/app/src/main/res/values-uk/strings.xml
index dac883c1..66791e00 100644
--- a/app/src/main/res/values-uk/strings.xml
+++ b/app/src/main/res/values-uk/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Калькулятор++</string>
     <string name="c_app_name_on_screen">Калькулятор + + (віконний режим)</string>
-    <string name="c_result_copied">Результат був скопійований до буферу обміну!</string>
     <string name="c_vars_and_constants">Змінні та константи</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">змінні</string>
     <string name="c_plot">Побудувати графік</string>
     <string name="cpp_precision">Точність результату</string>
     <string name="c_save">Зберегти</string>
     <string name="removal_confirmation">Підтвердження вилучення</string>
     <string name="c_var_removal_confirmation_question">Ви дійсно хочете вилучити змінну \'%s\'?</string>
-    <string name="c_var_name">Ім’я</string>
     <string name="c_var_value">Значення</string>
     <string name="c_var_description">Опис</string>
     <string name="c_var_create_var">Створити змінну</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">Значення має бути відсутнім або числом: якщо ви використовуєте параметри - визначте функцію замість цього!</string>
     <string name="c_var_name_clashes">Ім’я змінної не може бути зарезервованим системним ім’ям!</string>
     <string name="c_var_already_exists">Змінна з таким іменем вже існує!</string>
-    <string name="c_name_is_not_valid">Неприпустиме ім\'я змінної: ім\'я має починатися з літери, може містити літери, цифри та знак підкреслення(_).</string>
     <string name="c_history">Історія</string>
     <string name="c_char_is_not_accepted">Символ \'%s\' не допустимий у імені змінної!</string>
     <string name="cpp_deg">Градуси</string>
@@ -58,7 +53,6 @@
     <string name="convert_to_dec">Перетворити в dec</string>
     <string name="other">Інші</string>
     <string name="derivatives">Похідні/Інтеграли</string>
-    <string name="c_function_name">Ім’я</string>
     <string name="function_create_function">Визначити функцію</string>
     <string name="function_edit_function">Змінити функцію</string>
     <string name="function_already_exists">Функція з таким ім\'ям вже існує!</string>
diff --git a/app/src/main/res/values-vi/strings.xml b/app/src/main/res/values-vi/strings.xml
index 7211592b..5e3da880 100644
--- a/app/src/main/res/values-vi/strings.xml
+++ b/app/src/main/res/values-vi/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Máy tính ++</string>
     <string name="c_app_name_on_screen">Máy tính ++ (chế độ cửa sổ)</string>
-    <string name="c_result_copied">Kết quả đã được sao chép vào clipboard!</string>
     <string name="c_vars_and_constants">Biến và hằng</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">Các biến</string>
     <string name="c_plot">Vẽ đồ thị</string>
     <string name="cpp_precision">Độ chính xác của kết quả</string>
     <string name="c_save">Lưu</string>
     <string name="removal_confirmation">Xác nhận xoá</string>
     <string name="c_var_removal_confirmation_question">Bạn có thực sự muốn xóa \'%s\' biến?</string>
-    <string name="c_var_name">Tên</string>
     <string name="c_var_value">Giá trị</string>
     <string name="c_var_description">Mô tả</string>
     <string name="c_var_create_var">Tạo biến</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">Giá trị phải là một số hoặc để trống: nếu bạn có tham số - tạo ra một hàm để thay thế!</string>
     <string name="c_var_name_clashes">Tên biến xung đột với tên hàm!</string>
     <string name="c_var_already_exists">Biến có cùng tên đã tồn tại!</string>
-    <string name="c_name_is_not_valid">Tên của hằng số là không hợp lệ: tên phải bắt đầu với chữ cái, có thể chứa chữ cái, chữ số và gạch dưới.</string>
     <string name="c_history">Nhật ký</string>
     <string name="c_char_is_not_accepted">Ký tự \'%s\' không được chấp nhận trong tên biến!</string>
     <string name="cpp_deg">Độ</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">Chuyển đổi sang DEC</string>
     <string name="other">Khác</string>
     <string name="derivatives">Vi phân/tích phân</string>
-    <string name="c_function_name">Tên</string>
     <string name="function_create_function">Tạo hàm</string>
     <string name="function_edit_function">Chỉnh sửa hàm</string>
     <string name="function_already_exists">Hàm cùng tên đã tồn tại!</string>
diff --git a/app/src/main/res/values-zh-rCN/strings.xml b/app/src/main/res/values-zh-rCN/strings.xml
index 0d3c7ad9..1ced1c78 100644
--- a/app/src/main/res/values-zh-rCN/strings.xml
+++ b/app/src/main/res/values-zh-rCN/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++（悬浮）</string>
-    <string name="c_result_copied">结果已复制到剪贴板！</string>
     <string name="c_vars_and_constants">变量与常数</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">变量</string>
     <string name="c_plot">作图</string>
     <string name="cpp_precision">保留小数点后位数</string>
     <string name="c_save">保存</string>
     <string name="removal_confirmation">确认移除</string>
     <string name="c_var_removal_confirmation_question">您真的要移除变量 \'%s\' 吗?</string>
-    <string name="c_var_name">名称</string>
     <string name="c_var_value">值</string>
     <string name="c_var_description">描述</string>
     <string name="c_var_create_var">创建变量</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">值必须是一个数字或留空：如果有参数 - 请创建一个函数来代替！</string>
     <string name="c_var_name_clashes">变量名称与函数名称冲突!</string>
     <string name="c_var_already_exists">已存在相同名称的变量！</string>
-    <string name="c_name_is_not_valid">常数名称不正确：名称必须由英文字母开始，可以包含字母、数字和下划线。</string>
     <string name="c_history">历史</string>
     <string name="c_char_is_not_accepted">不能使用字符 \'%s\' 作为变量名称！</string>
     <string name="cpp_deg">度</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">转换为十进制</string>
     <string name="other">其他</string>
     <string name="derivatives">衍生工具/积分</string>
-    <string name="c_function_name">名称</string>
     <string name="function_create_function">创建函数</string>
     <string name="function_edit_function">编辑函数</string>
     <string name="function_already_exists">已经存在相同名称的函数！</string>
diff --git a/app/src/main/res/values-zh-rTW/strings.xml b/app/src/main/res/values-zh-rTW/strings.xml
index cfaaf586..78fecee3 100644
--- a/app/src/main/res/values-zh-rTW/strings.xml
+++ b/app/src/main/res/values-zh-rTW/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++（視窗模式）</string>
-    <string name="c_result_copied">計算結果已複製至剪貼簿！</string>
     <string name="c_vars_and_constants">變數與常數</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">變數</string>
     <string name="c_plot">繪圖</string>
     <string name="cpp_precision">計算結果精確度</string>
     <string name="c_save">儲存</string>
     <string name="removal_confirmation">刪除確認</string>
     <string name="c_var_removal_confirmation_question">你確定要刪除變數 \'%s\' 嗎？</string>
-    <string name="c_var_name">名稱</string>
     <string name="c_var_value">數值</string>
     <string name="c_var_description">描述</string>
     <string name="c_var_create_var">新增變數</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">數值必須是一個數目或留白：如果你有多個參數 - 新增一個函數來代替！</string>
     <string name="c_var_name_clashes">變數名稱與函數名稱衝突！</string>
     <string name="c_var_already_exists">已經有相同名稱的變數存在！</string>
-    <string name="c_name_is_not_valid">常數名稱無效：名稱必須以英文字母開頭，可以包含字母，數字及底線。</string>
     <string name="c_history">歷史紀錄</string>
     <string name="c_char_is_not_accepted">變數名稱不可使用字元 \'%s\' !</string>
     <string name="cpp_deg">度 (Degrees)</string>
@@ -57,7 +52,6 @@
     <string name="convert_to_dec">轉換為十進位 (dec)</string>
     <string name="other">其他</string>
     <string name="derivatives">微分/積分</string>
-    <string name="c_function_name">名稱</string>
     <string name="function_create_function">新增函數</string>
     <string name="function_edit_function">編輯函數</string>
     <string name="function_already_exists">相同名稱的函數已經存在！</string>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index e0e12ca3..68c0e737 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -2,16 +2,12 @@
 <resources>
     <string name="cpp_app_name">Calculator++</string>
     <string name="c_app_name_on_screen">Calculator++ (Window mode)</string>
-    <string name="c_result_copied">Result has been copied to the clipboard!</string>
     <string name="c_vars_and_constants">Variables And Constants</string>
-    <string name="c_clear">C</string>
-    <string name="c_vars">vars</string>
     <string name="c_plot">Plot graph</string>
     <string name="cpp_precision">Precision</string>
     <string name="c_save">Save</string>
     <string name="removal_confirmation">Removal confirmation</string>
     <string name="c_var_removal_confirmation_question">Do you really want to delete \'%s\' variable?</string>
-    <string name="c_var_name">Name</string>
     <string name="c_var_value">Value</string>
     <string name="c_var_description">Description</string>
     <string name="c_var_create_var">Create variable</string>
@@ -19,7 +15,6 @@
     <string name="c_value_is_not_a_number">Value must be either a number or left empty: if you have parameters - create a function instead!</string>
     <string name="c_var_name_clashes">Variable name clashes with function name!</string>
     <string name="c_var_already_exists">Variable with the same name already exists!</string>
-    <string name="c_name_is_not_valid">Name of the constant is not valid: name must start with letter, can contain letters, digits and underscore.</string>
     <string name="c_history">History</string>
     <string name="c_char_is_not_accepted">Character \'%s\' is not accepted in variable name!</string>
     <string name="cpp_deg">Degrees</string>
@@ -58,7 +53,6 @@
     <string name="convert_to_dec">Convert to dec</string>
     <string name="other">Other</string>
     <string name="derivatives">Derivatives/Integrals</string>
-    <string name="c_function_name">Name</string>
     <string name="function_create_function">Create function</string>
     <string name="function_edit_function">Edit function</string>
     <string name="function_already_exists">Function with the same name already exists!</string>
diff --git a/app/src/main/res/values/strings_non_translatable.xml b/app/src/main/res/values/strings_non_translatable.xml
index 0f1e98e0..7b520461 100644
--- a/app/src/main/res/values/strings_non_translatable.xml
+++ b/app/src/main/res/values/strings_non_translatable.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
+    <string name="cpp_kb_clear" translatable="false">C</string>
     <string name="cpp_kb_variables" translatable="false">π</string>
     <string name="cpp_kb_functions" translatable="false">ƒ</string>
     <string name="cpp_kb_operators" translatable="false">∂</string>