A: Let's play cards.
B: I don't know any card games.
A: I'll teach you one.
B: Okay. What will you teach me?
A: It's called poker.
B: Is it easy to learn?
A: Yes, it will only take about 30 minutes.
B: Okay. Teach me how to play.
A: We each get five cards.
B: Oh, look. I have four tens.
A: That's great, but you're not supposed to tell me.
B: Oh. Sorry. Okay, I don't have four tens..