diff --git a/src/App/Expression.cpp b/src/App/Expression.cpp
index 696fb23e02..e91d875e70 100644
--- a/src/App/Expression.cpp
+++ b/src/App/Expression.cpp
@@ -1732,14 +1732,14 @@ double num_change(char* yytext,char dez_delim,char grp_delim)
     char temp[40];
     int i = 0;
     for(char* c=yytext;*c!='\0';c++){
-        // skipp group delimiter
+        // skip group delimiter
         if(*c==grp_delim) continue;
-        // check for a dez delimiter othere then dot
+        // check for a dez delimiter other then dot
         if(*c==dez_delim && dez_delim !='.')
              temp[i++] = '.';
         else
             temp[i++] = *c;
-        // check buffor overflow
+        // check buffer overflow
         if (i>39) return 0.0;
     }
     temp[i] = '\0';
diff --git a/src/Base/Quantity.cpp b/src/Base/Quantity.cpp
index 65ef27c9bd..23a99443e0 100644
--- a/src/Base/Quantity.cpp
+++ b/src/Base/Quantity.cpp
@@ -317,14 +317,14 @@ double num_change(char* yytext,char dez_delim,char grp_delim)
     char temp[40];
     int i = 0;
     for(char* c=yytext;*c!='\0';c++){ 
-        // skipp group delimiter
+        // skip group delimiter
         if(*c==grp_delim) continue;
-        // check for a dez delimiter othere then dot
+        // check for a dez delimiter other then dot
         if(*c==dez_delim && dez_delim !='.')
              temp[i++] = '.';
         else
             temp[i++] = *c; 
-        // check buffor overflow
+        // check buffer overflow
         if (i>39) return 0.0;
     }
     temp[i] = '\0';
@@ -349,7 +349,7 @@ void Quantity_yyerror(char *errorinfo)
 namespace QuantityParser {
 
 #define YYINITDEPTH 20
-// show the parser the lexer method
+// show parser the lexer method
 #define yylex QuantityLexer
 int QuantityLexer(void);
 
diff --git a/src/Mod/Path/libarea/kurve/offset.cpp b/src/Mod/Path/libarea/kurve/offset.cpp
index 9be457f7a1..0d8f9e0f8c 100644
--- a/src/Mod/Path/libarea/kurve/offset.cpp
+++ b/src/Mod/Path/libarea/kurve/offset.cpp
@@ -168,7 +168,7 @@ namespace geoff_geometry {
 	static Kurve eliminateLoops(const Kurve& k , const Kurve& originalk, double offset, int& ret) {
 		// a simple loop elimination routine based on first offset ideas in Peps
 		// this needs extensive work for future
-		// start point musn't disappear & only one valid offset is determined
+		// start point mustn't disappear & only one valid offset is determined
 		//
 		// ret = 0 for ok
 		// ret = 2 for impossible geometry