英语四级应掌握的20个短语词汇：
1. on no account(=in no case, for no reason)绝不要，无论如何不要(放句首时句子要倒装)
2. accuse…of…(=charge…with; blame sb. for sth. ; blame sth. on sb. ; complain about) 指控，控告
3. be accustomed to (=be in the habit of, be used to)习惯于。
4. for certain of (=for sure )肯定地，有把握地
5. by chance(=accidentally, by accident)偶然
6. at will 随心所欲
7. access(to) (不可数名词) 能接近，进入，了解
8. by accident(=by chance, accidentally)偶然地，意外. Without accident(=safely) 安全地，
9. of one’s own accord(=without being asked; willingly; freely)自愿地 ,主动地
10. in accord with 与…一致 . out of one’s accord with 同…。不一致
11. take…into account(=consider)把..。考虑进去
12. give sb. an account of 说明， 解释 (理由)
13. with one accord (=with everybody agreeing)一致地
14. be acquainted with(=to have knowledge of) 了解; (=to have met socially) 熟悉
15. act on 奉行，按照…行动; act as 扮演; act for 代理
16. (be) abundant in(be rich in; be well supplied with) 富于，富有
17. in accordance with (=in agreement with) 依照，根据
18. on one’s own account
1) 为了某人的缘故， 为了某人自己的利益
2) (=at one’s own risk) 自行负责
3) (=by oneself)依靠自己
19. account for (=give an explanation or reason for) 解释， 说明。
20. on account of (=because of) 由于，因为。