We seem to be going round in circles here. If you do want to learn perl, read and understand the replies you've previously been given, work (yes, work. Don't just read them, make sure you understand what they're saying and how the code works) through the examples given in Getting Started with Perl from the tutorials section. If there is something you don't understand, you're going to have to specifically tell us, otherwise we'll never know.

My advice would be to stop posting exam questions and actually spend your time learning this. You say you have an exam to do, was there was an associated course? If so you should have notes. Do you have a teacher of some kind you could ask?