/Lisa|Bart/  #matches either Lisa or Bart by using the | (or) operator
/Lisa\sBart/ #matches Lisa then a whitespace character and then Bart
/\w{5}/      #matches 5 alphanumeric/word characters in a row
/sub\s+\w*{/ #matches the word sub then one or more spaces and then
             #0 or more alphanumeric characters followed by a {
/\d{3}-\d{4} #matches a phone number of the form 555-1234
             #3 numbers followed by a - followed by 4 numbers
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A great way to test just what a given pattern matches is the program below:

#!/usr/bin/perl
while(<>){
    print if m!your pattern here!;
}

All you have to do is drop your test pattern into place. Then run the program and type a line of text in at a time. If the pattern matches it will echo the line of text to the screen. When you have played with it enough simply type Ctrl-C.

You should now take some time to learn about split and join