Back porting changeset db302b88fdb6 to 3.4 branch, which fixed multiple documentation typos.

Related Issues:

#issue21528
#issue24453
diff --git a/Doc/howto/regex.rst b/Doc/howto/regex.rst
index fbe763b..9ae04d7 100644
--- a/Doc/howto/regex.rst
+++ b/Doc/howto/regex.rst
@@ -852,7 +852,7 @@
 problem.  Both of them use a common syntax for regular expression extensions, so
 we'll look at that first.
 
-Perl 5 is well-known for its powerful additions to standard regular expressions.
+Perl 5 is well known for its powerful additions to standard regular expressions.
 For these new features the Perl developers couldn't choose new single-keystroke metacharacters
 or new special sequences beginning with ``\`` without making Perl's regular
 expressions confusingly different from standard REs.  If they chose ``&`` as a