knock off 和knock over的用法

ask for 是固定搭配 有请求、要求的意思,这里是指“要钱”
当knock off和knock over同时在表示“撞倒”意思的时候,knock over一般就是指撞倒（+ed被动）,比如说A boy was knocked over by a passing car but was fortunately unhurt.而knock off则指从某个地方（被）撞倒,如A boy was knocked off his bike by a passing car but was fortunately unhurt.knock off:
knock off 更强调从原有的位置消失；而knock over 更强调姿态上的歪斜

1 knock off work
e.g.The King's health compels him to knock off work.国王的健康状况迫使他不得不停止工作.
2 貌似没有i have been off的说法吧...

knock off
基本翻译
vt.敲落(中止)
网络释义
knock off:停工|击倒|把敲掉
knock-off:敲落|停止|除去
knock_off:自动断开
knock down ['nɔkdaun]
基本翻译
击倒,撞倒,(投篮)命中
网络释义
knock down:撞倒|击倒|拆除
knock-down:卸开|击倒的|药效量
knock down sb:撞倒某人
标准的答案哦~

此类结构属于
Vt+adv构成的短语.其中动词一般是单音节词,而副词表示动作的结果.
动词常见的有：
get,cut, give, turn, put, knock等
副词常见的有：in/out; up/down; on/off; away等
一般情况下,名词宾语可放副词前,后都可；
但如果是代词,就只能放在副词前了.
如：
put it on
put the coat on
put on the coat

knock off 是敲落,knock down是击倒、撞倒的意思,其实基本都一样,但是knock off还有中止的意思,而knock down还可以指投篮命中

你难道把这个当成词组去背吗?

〈非正〉将…击打掉, 碰撞掉
She knocked the vase off by accident.
她不小心把花瓶打掉了。
〈口〉(使)停止
Let's knock off now.
现在让我们歇一下吧。
〈非正〉降低
If you take both dresses, I'll knock ￡2 off.
你要是两套衣服都买,...

好问题!对,Get off work 是正式英语,略有下班之意.
Knock off 是俚语,作为俚语,knock off 有几个不同意思：
1.下班,休息,或停止.如：Let’s knock off work at noon.
2.完成,做完,草草了事：That author knocked off a book a year early.
3.除掉,减少：She is overweight; she needs to knock off 12 pounds in a month.
4.劫持：The robber knocked off a bank in this neighborhood.
5.复制或模仿：This phone is a knock-off of Apple’s iPhone.

It was evening.Jane was watching TV at home.Suddenly she heard someone knocking at the door.Then Jane went to open the door.A man came in and knock her off.When Jane was sttruggling shen knock a big vase off.Her neighbour heard the noise and came to help her.Finally Jane was survived.