1.back and forth 来回地,反复地
2.back of 在后面
3.back up后备,支援
4.bare of几乎没有,缺乏
5.be able to do能够
6.be around差不多
7.be available to sb可用,可供
8.be bound to一定
9.be capable of doing能够
10.be concerned with 关心…，涉足…
11.be dying to渴望
12.be fed up with受够了be tired of
13.be in hospital 住院
14.be in season 上市的/in peak season旺季
15.be in the mood to do sth 想做
16.be pressed for time时间不够
17.be tied up with忙于
18.be under the weather 身体不好
19.beat around the bush 拐弯没角
20.beat the crowd 避开人群
21.before long 不久以后
22.behind schedule 误点
23.bent on sth 下定决心做…
24.beside point 离题的,不相干的
25.beyond one's ability超越某人的能力
26.beyond question 毫无疑问
27.book on reserve 须留的图书
28.booked up 订完了
29.bound for开往
30.break down抛锚
31.break though突破
32.break up with和某人分手
33.bring about 使…发生
34.bring someone up to date将最新消息告诉某人
35.by accident 偶然
36.by air 通过航空途径
37.by all means 尽一切办法,务必
38.by and by 不久,迟早
39.by chance 偶然,碰巧
40.by far 最,得多
41.by hand 用手,用体力
42.by itself 自动地,独自地
43.by means of 用,依靠
44.by mistake 错误地,无意地
45.by no means 决不,并没有
46.by oneself 单独地,独自地
47.by reason of 由于
48.by the way 顺便说说
49.by virtue of 借助,由于
50.by way of 经由,通过方法