14.We often go to Hongshan Zoo _______ Saturday.

13. The first class begins _______ eight o’clock in our school.

12. The Chinese New Year usually comes ______February.

11. It’s very cold ______ winter in Nanjing.

10. Every day Millie spends half an hour ______(read) English.

C: 用适当的介词填空。

9. Thank you very much for ______(write) to me.

8. My brother often ______(play) basketball on Wednesday afternoon.

7. Lily always helps her mother clean the house. She is very______(help).

6. Susan swims very well. She is a good ________.(swim)

5. My father and my mother are b_______ doctors.

B: 用所给单词的适当形式填空。