prevent/stop/keep/protect

prevent, stop, keep与protect四者的常见结构为：

prevent ...(from) doing sth.；

stop ...(from) doing sth.；

keep ...from doing sth.; 均表示“阻止……做某事”。

上述三个结构中，在主动语态中stop 与prevent后可省去from，但在被动语态中不可省略; 而keep ...from ...中的from在任何情况下都不能省略。

prevent ...(from) doing sth.；

His words can’t prevent us from buying books.他的话不会阻止我们买书。

The heavy rain prevented us going on,but we didn’t lose heart.大雨阻止我们前进，但是我们不灰心丧气。

在被动语态中，from都不可省。

The rain prevented us (from) going there.

We were prevented by the rain from going there.

We should take measures to prevent the river from being polluted.

The heavy rain prevented us from going there.这场大雨使我们没能到那里去。

Lynn’s parents tried to stop her seeing him.林恩的父母企图阻止她和他见面。

protect ...from ...表示“保护……不受……侵袭；阻挡；防御”。from后接能带来伤害或损害的事物。

protect ...from ...

保护……免受……，后接较小的事情或危害， An umbrella will protect you from the rain.雨伞可以保护你不至于淋雨。

Trees should be well protected from the cold during winter.冬天要保护好树木以防冻坏。

You should protect the children from the cold.  你们应该保护孩子不让其受冻。

He raised his arm to protect his face from the blow.  他抬起手臂保护脸免受打击。

He wore dark glasses to protect his eyes from the strong sunlight.  他戴墨镜以防强烈的阳光刺伤眼睛。

Rub some of the cream into your skin to protect it from the sun.  在皮肤上擦些防晒霜，以防太阳晒。

The new measures are designed to protect the public from people like these.  新措施旨在保护公众免遭这类人的伤害。

You should protect the children from catching cold . 你应该防备孩子们受凉。

What parents shouldn't do is protect girls from losing. 父母不应该总是保护女儿，不让她们失败。

May God protect you from harm this night.愿上帝保佑你今夜免受伤害。

Net the fruit trees to protect them from birds.用网盖住果树以免遭鸟害。

Skiers wear goggles to protect their eyes from the sun.  滑雪者都戴上护目镜使眼睛不受阳光伤害。

联想拓展

protect ...against ...后接较大的事情，如：战争、灾害、重税、威胁等。

The cat uses its claws to protect itself against enemies. 

那只貓用爪子保护自己，抵御敌人。

These tree belts effectively protect the farmland against shifting sand. 

这些防护林带有效地保护了农田，使之免受流沙侵袭。

keep ...from doing sth. 这里from不可省略。

This plan will be kept from being carried out.这个计划将被阻止实施。

You won’t keep the things from happening.你不能阻止事情发生。

单项填空

1. Some policemen should be sent to          them         the trees.

A. prevent; to cut down         

B. stop; cutting down

C. keep; to cut down           

D. keep; cutting down

解析:选B。句意为：应该派一些警察去阻止他们砍伐树木。keep/prevent/stop ... from doing sth.阻止……做某事,其中keep ...from doing sth. 中的from不可省略。故选B。

2. The heavy rain _____ us visiting the attractive lake,but we didn’t _____.

A.prevented;lose the heart

B.prevented;lose heart

C.kept;lose the heart

D.kept;lose the heart

解析:第一分句的意思是:大雨使得我们不能参观那湖水，可以用prevented /kept sb. from doing sth.，第二分句意思是:我们并没有灰心丧气，用lose heart表达。选 B项。

答案:B