9. What's for Lunch?

A: What do you have for lunch, David?

B: I have a peanut butter and jelly sandwich.

A: That sounds good. I have tuna.

B: Tuna is good too, Daniel.

A: I like jelly. Do you want to trade?

B: Sure. I like tuna.

A: This trade is good for both of us.

B: Yes, it is. Thanks, Daniel.