1. a big headache令人頭痛的事情
2. a fraction of 一部分
3. a matter of concern 焦點
4. a series of 一系列,一連串above all 首先,尤其是
5. absent from不在,缺席
6. abundant in富于
7. account for 解釋
8. accuse sb. of sth.控告
9. add to增加（add up to）
10. after all 畢竟,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與...相反
15. all at once 突然,同時
16. all but 幾乎;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 令人滿意的;可以
21. all the same 仍然,照樣的
22. all the time 一直,始終
23. angry with sb. at/about sth.生氣,憤怒
24. anxious about/for憂慮,擔心
25. anything but 根本不
26. apart from 除...外(有/無)
27. appeal to 吸引，申訴，請求
28. applicable to適用于
29. apply to適用
30. appropriate for/to適當,合適
31. approximate to近似,接近
32. apt at聰明,善于
33. apt to易于
34. around the clock夜以繼日
35. as a matter of fact 實際上
36. as a result(of) 因此,由于
37. as a rule 通常,照例
38. as far as ...be concerned 就...而言
39. as far as 遠至,到...程度
40. as follows 如下
41. as for 至于,關于
42. as good as 和...幾乎一樣
43. as if 好像,防腐
44. as regards 關于,至于
45. as to 至于,關于
46. as usual 像平常一樣,照例
47. as well as 除...外(也),即...又
48. as well 同樣,也,還
49. ashamed of羞愧,害臊
50. aside from 除...外(還有)
51. ask for the moon異想天開
52. at a loss 茫然,不知所措
53. at a time 一次,每次
54. at all costs 不惜一切代價
55. at all events 不管怎樣,無論如何
56. at all times 隨時,總是
57. at all 絲毫(不),一點也不
58. at any rate 無論如何,至少
59. at best 充其量,至多
60. at first sight 乍一看,初看起來
61. at first 最初,起先
62. at hand 在手邊,在附近
63. at heart 內心里,本質上
64. at home 在家,在國內
65. at intervals 不時,每隔...
66. at large 大多數(shù),未被捕獲的
67. at last 終于
68. at least 至少
69. at length 最終,終于
70. at most 至多,不超過
71. at no time 從不,決不
72. at one time 曾經,一度;同時
73. at present 目前,現(xiàn)在
74. at someone's disposal 任...處理
75. at the cost of 以...為代價
76. at the mercy of 任憑...擺布
77. at the moment 此刻,目前
78. at this rate 照此速度
79. at times 有時,間或
80. aware of意識到
81. back and forth 來回地,反復地
82. back of 在...后面
83. back up后備,支援
84. bare of幾乎沒有,缺乏
85. be able to do能夠
86. be around差不多
87. be available to sb.可用,可供
88. be bound to一定
89. be capable of doing能夠
90. be concerned with 關心…，涉足…
91. be dying to渴望
92. be fed up with受夠了be tired of
93. be in hospital 住院
94. be in season 上市的/in peak season旺季
95. be in the mood to do sth. 想做
96. be pressed for time時間不夠