knock off
1．stop；leave work 中止（工作）；停工
Let's knock off early today and go to see a ball game．我们今天早点下班去看球赛。
We start work at eight and knock off at twelve．我们8点开始工作，12点收工。
What time do you knock off on Fridays？你们星期五什么时候下班？
2．deduct除去；扣去；减去
He knocked off ten percent from the price．他杀价10％。
When he received his money he found that five pounds had been knocked off for expenses incurred．当他收到钱时，他发现由于各种开支扣除了5镑。
3．compose（a poem， an article， a novel， etc．） rapidly and in a short time很快就写出（诗、文章、小说等）
He sat down and knocked off an article for the local paper in an hour．他坐下来在一小时内很快就给当地报纸写了一篇文章。
She knocked that article off in no time at all．那篇文章她一挥而就。
The boy knocked off his homework in 15 minutes and ran out to play tennis．这孩子在15分钟内匆匆写完作业就跑出去打网球了。
4．steal from； commit robbery at 偷窃；抢劫
They knocked off a bank．他们抢了一家银行。
The boy knocked off a necklace when the shop assistant wasn't looking．那个男孩在店员不注意时，偷了一条金项链。
5．eat up quickly吃得快
He knocked off two chops and a plateful of vegetables in about ten minutes and then asked for more．他在10分钟内就吃完两块排骨和一碟蔬菜，然后又要加菜。
6．obtain获得
He knocked off a Nobel prize．他获得了诺贝尔奖金。
7．take into custody； arrest拘留；逮捕
He was knocked off by the police．他被警察拘捕了。
8．murder谋杀
The gangsters knocked off Herman．歹徒谋害了海尔曼。
They say that the policeman got knocked off because he saw the raiders'faces．他们说那个警察被杀死了，因为他看见了强盗的面孔。