If this is production work in some fashion then using a module such as Text::Wrap as suggested above is the way to go. If this is a learning exercise or homework then we would like to see a little effort from you up front.

There are a number of ways of approaching the task:

• you could read the text into a string then use a regular expression to extract the required sub strings.
• you could use index and substr to parse and chop up the string
• you could parse the words into an array along with their lengths then use that to generate the output texts for different 'n's

Pick an approach. Write some code. If you have trouble, come back to us with what you've tried and we will help further. We don't generally do what looks like people's homework for them however so don't come back and say "how do I do it using option 3".