A. Once a month        
B. For a month
C. A month ago          
D. A month later

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.

1. In our school, very f_____ students go to school by car.
2. Jane n_____ goes to school on foot. She usually takes a bus to school.
3. Please wait for (等待) a little w_____. I have to put on my running shoes.
4. —How often does Jane go to the park? 
   —O_____ a week.
5. —Can you tell me something about your school l_____ in America?
    —Sure.

1. — How often does he go to the movies?
    — T_____ a month.
2. It takes me only ten m_____ to get to school from home.
3. — Where are you doing the day after t_____?
    — I'm staying at home.
4. — What are you doing on Sunday?
    — I'm fishing with my uncle the w_____ day.
5. I can't help you do your homework because I have tennis t_____.