根据句意和首字母或汉语提示完成单词。

1. — How often does Mary exercise? 

    — She exercises t________ a week.

2. — Could I b_______ your bike?

    — Yes. Here's the key.(钥匙)

3. It often rains in s________ China in summer.

4. Here are two _________(薄片) of bread.

5. Her writing __________(习惯) are very good.

6. I was really busy. I spent the w________ morning doing my homework.

7.We must read ____________(说明) before taking medicine.

8. He won first prize in the singing c_________.

9. Her favorite subjects are c____________ and physics.

10. My cousin b_________ a teacher in 2008.