根据句意和提示写出单词的正确形式。

1．A hundred years is called a c_________．

2．If you go to Beijing，you'll see a lot of a_________ buildings，such as the Palace Museum and the Great Wall．

3．I asked him to help me，but he r_________．This made me feel sad．

4．Mr. Smith has taught for many years，so he has much e_________ in teaching．

5．Don't tell anyone about my plan．Keep it a s_________．

6．Today_________（广告）are very important in business．

7．The present is _________（专门）chosen for your mother．

8．what _________（引起）the accident last night?

9．Would you please _________（去取来）my handbag?

10．Mrs. Green bought some shampoo，toothpaste and _________（毛巾）for the family．