English

If you talk to a man in a language he understands, that goes to his head.  If you talk to him in his own language, that goes to his heart.
- Nelson Mandela

Now for some humour.
I found a great resource for teaching idioms - if you have adults who have a sense of humour. It drives home how misinterpretations occur that we don't realize can happen.

party pooper

And another - for those teaching ESL to children and learning all the Christmas songs.

See if you can figure out this one.