51. at a loss 茫然,不知所措
52. at a time 一次,每次
53. at all costs 不惜一切代价
54. ask for the moon 异想天开
55. at all events 不管怎样,无论如何
56. at all times 随时,总是
57. at all 丝毫(不),一点也不
58. at any rate 无论如何,至少
59. at best 充其量,至多
60. at first sight 乍一看,初看起来
61. at first 最初,起先
62. at hand 在手边,在附近
63. at heart 内心里,本质上
64. at home 在家,在国内
65. at intervals 不时,每隔...
66. at large 大多数,未被捕获的
67. at last 终于
68. at least 至少
69. at length 最终,终于
70. at most 至多,不超过
71. at no time 从不,决不
72. at one time 曾经,一度;同时
73. at present 目前,现在
74. at someone's disposal 任...处理
75. at the cost of 以...为代价
76. at the mercy of 任凭...摆布
77. at the moment 此刻,目前
78. at this rate 照此速度
79. at times 有时,间或
80. aware of意识到
81. back and forth 来回地,反复地
82. back of 在...后面
83. back up后备,支援
84. bare of几乎没有,缺乏
85. be able to do能够
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能够
90. be concerned with 关心…，涉足…
91. be dying to渴望
92. be fed up with受够了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时间不够
97. be tied up with忙于
98. be under the weather 身体不好
99. beat around the bush 拐弯没角
100. beat the crowd 避开人群