看图，选择合适的介词填空。

- Can I help you, Tim?
- Yes. I need a ruler. Give me a ruler, please.
- Where is it?
- It's_________the bag. Give me a pencil case, please.
- Where is it?
- It's_________the table. Give me a ball, please.
- Where is it?
- It's_________the table.
- Here you are.
- Thank you. Oh, where is my chair? I can't find it.
- Don't worry. It's here,_________the table.