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.