一、详细释义：


n.

爆震声


例句：

What's that knock I can hear from the engine?

我听到发动机有爆震声是怎么回事啊?


敲；敲打 [C]


例句：

A sudden knock at the door drew us up sharply in our conversation.

一阵突然的敲门声使我们停止了谈话。


例句：

I heard a knock at the door.

我听到了敲门声。


v.

敲；打；击 [I,T]


例句：

Knock that nail in, it's sticking out dangerously.

把那钉子敲进去，它伸出来很危险。


例句：

If I see that kid in my orchard again, I'll knock his head off.

我要是再看到那个小孩到我的果园里来，我就揍他。


批评 [T]


例句：

Why must you knock your hometown instead of boosting it?

你为什么一定要批评你的家乡而不为之吹嘘?


例句：

Tom's supervisor has kept knocking him 3 days for the failure of financial plan.

由于财务计划失败，汤姆的上司已经数落他三天了。


撞 [I,T]


例句：

The truck was out of control and knocked a dog to death.

失控的卡车将一只小狗撞死了。


例句：

The baby was knocked from his father's arms.

婴儿被从他父亲的怀中撞落。


（心）怦怦跳 [T]


例句：

After a long marathon running,my heart is knocking rapidly.

一场长距离马拉松跑下来，我的心脏怦怦直跳。


二、词义辨析：


knock,tap,rap,pat

这些动词均有“敲、击”之意。 knock指用拳头或其它器械猛敲或猛打；也指用手轻敲某物。 tap多指慢慢地连续地轻击或轻拍。 rap指用手指或木棒等快速地轻敲或急拍。 pat指用手轻拍以示同情、赞同或爱抚。


三、相关短语：


knock about

碰撞;到处流浪,厮混;漫游;接连打击;冲击;粗暴对待


knock against

偶然遇到,碰到


knock back

喝光,花光,花费


knock down

击倒;撞倒;击落;使屈服;拆除;拆卸;迫使降低;获得


knock off

v. 1.撞倒，打掉 2.减去 3.停止，歇工


knock out

v. 1.用锤等敲掉；打掉 2.使昏迷 3.击倒 4.淘汰 5.使不能使用；毁坏 6.使筋疲力尽；使竭尽全力 7.粗略地〔匆匆地〕创作〔完成〕 8.使震惊 9.引起共鸣


knock over

v. 1.碰翻；打倒 2.使吃惊 3.轻易击败 4.偷窃；抢劫 5.快速完成


knock up

敲门叫醒；伤害，使烦恼，使生病；挣到，赚到；赶做，赶制


knock cold

［口］打昏； 使昏倒


knock on

敲击, 结束


knock-on effect

n. 撞击作用


四、参考例句：


Knock off every objection.

排除一切反对意见。


Knock before you enter.

进来前先敲门。


Knock at the door.

敲门。


Knock it off.

别说了。


Knock yourself out.

请随意别客气。


Come in, do not knock.

进来，不要敲门。


Knock out holiday gift shopping.

淘节日礼物。


Someone is knocking at the door.

有人在敲门。


You should knock before you came in.

进来前你应该先敲门。


I heard a knock at the door.

我听到了敲门声。