as to 至于，关于;
as well也，一样
as yet迄今，到目前为止
aside from 除┄之外;
associate … with…由……联想到…，把…联系起来
association with与……的交往
at a disadvantage处于不利地位
at a loss不知所措
at a time每次，一次
at all 丝毫,根本;
at any moment即使，随时。
at first 首先,开始的时候;
at large未被捕获的,大多数;
at last 终于，最终;
at least至少
at length 最终,详细地;
at most最多
at no time从不，决不
at one time曾经，从前曾
at the cost of以……为代价
at the least 至少;
at times有时,间或;
at…speed以……的速度
attend on 照顾，侍候;
attribute … to 把……归于
back up 后退，支持;
base on 基于
be able to能够，胜任
be about to正打算
be accustomed to习惯于
be associated with 与……有关，与……有关系
be aware of 意识到;
be capable of 有能力干;
be caught 遇到，陷入
be committed to被交给┄,答应承担┄义务;
be confined to 限制在,局限于;
be confined/be restricted受……限制
be dedicated to 奉献,献给;
be devoted to 被用于，贡献给