}
-=head2 How do I substitute case insensitively on the LHS while preserving case on the RHS?
+=head2 How do I substitute case-insensitively on the LHS while preserving case on the RHS?
X<replace, case preserving> X<substitute, case preserving>
X<substitution, case preserving> X<s, case preserving>
Notice how the second substitution stopped matching as soon as it
encountered "y ". The C<*?> quantifier effectively tells the regular
expression engine to find a match as quickly as possible and pass
-control on to whatever is next in line, like you would if you were
+control on to whatever is next in line, as you would if you were
playing hot potato.
=head2 How do I process each word on each line?