6. abundant in富于
7. account for 解释
8. accuse sb. of sth.控告
9. add to增加(add up to)
10. after all 毕竟,究竟
11. agree with同意
12. ahead of time / schedule提前
13. ahead of 在...之前(ahead of time 提前)
14. alien to与...相反
15. all at once 突然,同时
16. all but 几乎;除了...都
17. all of a sudden 突然
18. all over again 再一次,重新
19. all over 遍及
20. all right 令人满意的;可以