There are numerous ways to achieve what you want. For the substitution itself, the only thing that might be slightly beyond a pure beginner's knowledge, the first idea that comes to mind is to use the substitution operator, s///. You'll find detailed documentation on this in this chapter Regexp Quote Like Operators of the perlop document. Look in particular at the s/PATTERN/REPLACEMENT/msixpodualgcer sub-chapter and at the e option modifier.