根据句义完成句中已给出首字母的单词。将每个完整的单词写在各小题右边的横线上。

1. December is the t__________ month of the year.                           1. _______________

2. We should make a contribution to p___________ the environment.       2. _______________

3. It is usually very c___________ in the supermarket on Sundays.          3. _______________

4. Could you tell me how he is getting a______  _ with his studies.        4.______________

5. My workmate usually makes up a good e___  ___ for his being late every time. 70._________