用所给词的适当形式填空。

1. Thank you very much for              (help) me so much.

2. When I             (walk) in the street, I             (meet) him.

3. Liu Hua             (buy) a grammer book yesterday.

4. His son             (study) English in England last year.

5. Can you finish             (do) your homework at 10?

6. They             (go) out for a walk if it doesn't rain.

7. He             (say) he will go to Beijing.

8. They             (do) their lesson this time yesterday.

9. Mr Smith wanted             (have) his holiday in London.

10. He             (not watch) TV every day.

在李小姐所购买的全部投资产品中，风险最大和最小的分别是( )。

A．股票；可转换债券

B．可转换债券；国债

C．货币市场基金；股票

D．股票；国债