Joke

Two goldfish in a bowl talking:
Goldfish 1: Do you believe in God?
Goldfish 2: Of course, I do! Who do you think changes the water?

This one (the goldfishes joke) I explain it on the Sant-Jordi concert. We only said it on the first time because after they said to us that there insn't time for the jokes. But equally, when it was my turn to say the joke, nobody was listening (because nobody understood the jokes... ).