Updated for Summer 2021

Signed-off-by: Prof. Ronald Moore <ronald.moore@h-da.de>

recursiveDescentParsers/cplusplus/README.md

@@ -22,7 +22,7 @@ There are (or will be some day) subdirectories here:
      including the new (C++17) `std::variant<>` template. 
      Testing is also more extensive.
      This is meant mostly as a preparation for larger projects where
-     software engineering aspects becomes more important 
+     software engineering aspects become more important 
      whereas the version in `interpreter` (see above) is meant
      to get down to recursive descent parsing as quickly as possible.