文档介绍：a big headache令人头痛的事情
a fraction of 一部分
a matter of concern 焦点
a series of 一系列，一连串above all首先,尤其是
absent from 不在，缺席
abundant in 富于
account for 解释
accuse sb. of
add to 增加（add up to）
after all毕竟，究竟
agree with 同意
ahead of time / schedule 提前
ahead of 在…之前（ahead of time 提前）
alien to与…相反
all at once 突然，同时
all but几乎滁了…都
all of a sudden 突然
all over again 再一次，重新
all over 遍及
all right令人满意的;可以
all the same仍然,照样的
all the time 一直，始终
angry with sb. at/about ，愤怒
anxious about/for 忧虑，担心
anything but 根本不
apart from 除..夕卜（有/无）
appeal to吸引，申诉，请求
applicable to 适用于
apply to 适用
appropriate for/to 适当，合适
approximate to 近似，接近
apt at聪明，善于
ap45. as to 至于，关于
as usual像平常一样，照例
as well as 除..夕卜（也），即...又
as well同样，也，还
ashamed of 羞愧，害臊
aside from 除...夕卜（还有）
ask for the moon 异想夭开
at a loss茫然，不知所措
at a time 一次，每次
at all costs不惜一切代价
at all events不管怎样，无论如何
at all times 随时，总是
at all丝毫（不），一点也不
at any rate无论如何，至少
at best充其量，至多
at first sight乍一看，初看起来
at first最初，起先
at hand在手边，在附近
at heart内心里，本质上
at home在家,在国内
at intervals不时,每隔…
at large大多数，未被捕获的
at last 终于
at least 至少
at length最终，终于
at most至多,不超过
at no time从不，决不
at one time曾经，一度洞时
at present 目前，现在
at someone's disposal 任…处理
at the cost of以…为代价
at the mercy of 任凭...摆布
at the moment 此亥U,目前
at this rate 照此速度
at times有时，间或
aware of 意识到
back and forth来回地，反复地
back of 在...后面
back up后备，支援
bare of几乎没有，缺乏
be able to do 能够
behind schedule 误点
bent on ...
beside point离题的，不相干的
beyond one's ability 超越某人的能力
beyond question 毫无疑问
book on reserve 须留的图书
booked up 订完了
bound for 开往
break down 抛锚
break though 突破
break up with 和某人分手 be through with / be finished with
bring about 使…发生
bring someone up to date 帮某人赶上 help someone catch up
by accident 偶然
by air通过航空途径
by all means尽一切办法，务必
by and by不久，迟早
by chance 偶然，碰巧
by far最,…得多
by hand用手,用体力
by itself自动地，独自地
by means of 用，依靠
by mistake错误地，无意地
by no means决不,并没有
by oneself单独地，独自地
by reason of 由于
by the way顺便说说