課本中不會(huì)教你的[K]424　knock，knock at，knock down和knock into

424　knock，knock at，knock down和knock into

① knock可用作及物動(dòng)詞和不及物動(dòng)詞，意為“敲，擊，撞”。結(jié)構(gòu)為：

knock sth. off撣掉（灰塵等）

knock sb. on the head擊某人的頭

knock oneself on sth.（自己）撞到

She knocked the dust off his coat. 她把他上衣的塵土撣掉。

He knocked the boy on the head. 他朝那個(gè)男孩頭上猛擊。

He knocked himself on a tree. 他撞到了一棵樹上。

② knock at/on意為“敲（門、窗等）。

Who is knocking at the door？誰(shuí)在敲門？

Somebody is knocking on the window. 有人在敲窗。

③ knock down意為“撞倒，打倒，擊落，拆除”。

The boy was knocked down by a car. 那男孩被一輛汽車撞倒了。

They knocked down three enemy planes yesterday. 他們昨天擊落了3架敵機(jī)。

提示

knock down是“及物動(dòng)詞+副詞”構(gòu)成的短語(yǔ)，可以說(shuō)knock+名詞+down或knock+down+名詞，但只能說(shuō)knock+代詞+down。同類動(dòng)詞短語(yǔ)還有：turn down，turn on，take off，put away，throw away，break down等。

He knocked the dog down. 他把那條狗打倒了。

④ knock into sb.意為“撞到某人身上”，knock sth. into意為“把……敲進(jìn)”。

If you knock into someone，you should apologize to him or her. 如果你撞到了某人身上，你應(yīng)該向他或她表示道歉。

He knocked a nail into the wall. 他把一顆釘子敲進(jìn)墻里。

比較

knock sb. out把某人擊昏

knock sb. down把某人擊倒