单词拼写。

1．In a library,books and magazines are usually c________ by subject.

2．Finally,the Red Army finished the worldfamous Long March by o________ countless difficulties.

3．There is no doubt that the 17th National Congress of CPC is of great s________ to China's future.

4．His words c________ an unfriendly attitude made the people present annoyed.

5．She often c________ to her boss about her being paid badly.

6．He is expected to ________(阐明)his position at the conference.

7．Do make a careful ________(选择)before you act.

8．There have been many ________(冲突)though the world is in peace generally.

9．Her style of writing is rather ________(独特的)．

10．The invention of the printing press caused a ________(革命)in learning.

长三角和环渤海地区建立化学工业不同的主导区位因素是什么？