David: I want to take some photos in the park, but I can't find my camera. Where is it, mum?
Mum: Is it on the computer?
David: No, it isn't. It was there yesterday (昨天).
Mum: Ah, I see. It's near the computer.
David: Thanks. I need some films. Where are they?
Mum: They are in the desk.
David: I've got it. But where's my bag? It was on the chair a moment ago.
Mum: It's on your bed. Can you see it?
David: Yes. Bye, mum.
1. What does David want to do in the park?
2. Where is the camera?
3. Where are the films?
4. Is David's bag on the chair?
