1. back to back : 背靠背；
2. turn one's back on : 背弃, 抛弃；
3. back down : 放弃要求, 取消前言；
4. back and forth : 来回地；
5. back up : 支持；
6. see the back of : 看(某人)离开, 赶走[摆脱](某人)；
7. be on one's back : 仰卧, 生病卧床；
8. back of : 在...后边；
9. with one's back to the wall : 困兽犹斗地；
副词
及物动词
名词
电影
培训
假期
副词用法（ADVERB USES）
In addition to the uses shown below, back is also used in phrasal verbs such as ‘date back’ and ‘fall back on’.
1. (American football) the position of a player on a football team who is stationed behind the line of scrimmage
2. a support that you can lean against while sitting
e.g. the back of the dental chair was adjustable
Synonym: backrest
3. the part of a garment that covers the back of your body
e.g. they pinned a `kick me' sign on his back
4. the protective covering on the front, back, and spine of a book
e.g. the book had a leather binding
Synonym: bindingbook bindingcover
5. the side that goes last or is not normally seen
e.g. he wrote the date on the back of the photograph
Synonym: rear
6. the posterior part of a human (or animal) body from the neck to the end of the spine
e.g. his back was nicely tanned
Synonym: dorsum
7. the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
e.g. the fall broke his back
Synonym: spinal columnvertebral columnspinebackbonerachis
8. the part of something that is furthest from the normal viewer
e.g. he stood at the back of the stage
it was hidden in the rear of the store
Synonym: rear
9. (football) a person who plays in the backfield