PPT with sound files for identifying english emotion and stresses.
Adjoined file 'I shouldn't have done that' Pictures showing someone regretting something. I make the kids guess what's going on and try to make a sentence using 'I regret .... ' 'I should/shouldn't have....' 'if only...' and then show them the example sentence in the following slide, then get them to alter it so we have one version for each of the three sentence structures.
After that we draw a picture of something we regret doing, and swap with someone to write a sentence. The example I do on the board for this is shooting a man in the head, and then I say 'I regret killing a man' and we sing a bit of Bohemian Rhapsody cause they love that and they're teenage boys. Usually it is more fun if you tell them to make something up.
:D

Another idea is to do roleplay in pairs. Students think about something they regret and write a 5 minute interaction about what they did and the other should say "you shouldn't have done that" and gives advice. This can be read out in front of the class. You can start by giving an example first so they can model it on your example.