备考英语四级的过程中,语法是大家认为最难的地方。下面是小编给大家分享的关于英语四级常考的语法要点,大家可以作为学习参考。

非谓语动词

(一) 分词

现在分词和过去分词的区别

①、用于句首作状语,现在分词表示主动,过去分词表示被动

例:Won its war for independence in 1783, the United States then struggled to establish its owneconomic and financial system.

分析:分词作状语,主要看是主动还是被动,美国赢得应该是主动,所以改won为winning

②、用于名词后面作后置定语,现在分词表示主动,过去分词表示被动

例:In the nineteenth century the Mohave Indians lived in the Northern Hemisphere grew their crops on river bottom lands.

分析:生活在什么地方的人,人生活是主动,因此改为living

一些动词后面必须用doing

对于加doing的词来说,考试中一般出现一个,下面这些词都是要加doing的,请考生牢记。

mind, finish, enjoy, celebrate, adjust ,advocate, suggest,delay, quit,forgive(原谅),tolerate,avoid, escape(逃避),spend+名词+doing;

have trouble/difficult/a problem/ +doing

例:Long before the dawn of recorded history, humans celebrated to harvest their crops.

分析: harvest应改为harvesting。及物动词celebrate直接带名词、名词短语或动名词短语作宾语,故将to harvest改为harvesting。

例:Some experts have advocated to bring that country into the talks, to revive the intermittent dialogue that began after the 1967 Middle East War.

分析:advocate 后面直接跟doing, 改为advocate bringing

(二) 不定式

A. 动词不定式的省略

①、help后面可以省略to

help to do

help sb. to do

例:A good exercise program helps teach people to avoid the habits that might shorten the lives.

分析:the应改为their. 定冠词在句中不如代词所有格明确,如果lives后面有定语就可以用the。

②、使役动词后面要省略to, 这样的动词只有三个

make, let,have sb. do sth

注意get不是使役动词,get sb. to do sth.

例:A conductor used signals and gestures to let the musicians to know when to play various parts of a composition.

分析:let是使役动词,后面不需要to, to know改为know

③、感官动词

hear, feel, watch, see, notice, observe ,see sb do sth. 强调过程

see sb doing sth 正在做某事

B. 动词不定式的固定用法

(1)表示第一人

the first woman to do sth.

(2)表示迫使的动词

一般考三个, allow/ enable/ call, +sb. + to do

例:Besides providing clues to the nature of atoms, mineral analysis allows to speculate geologists about the ancient Earth

分析:allow...to do是固定短语,allow的宾语应在不定式之前,即把改为: allow geologists to speculate。

(3)表示倾向…的形容词

be more likely to do 更有可能作某事

be inclined to do倾向于做某事

be liable to do 易于…的

be apt to do

(4)表示目的的名词,一共有7个这样的词,这一条也是最重要的。

固定的句式:

the purpose , the purpose of sth is to do sth.

the objective 目标

aim

goal

reason理由

function功能

intension意图

例:The function of Louis Sullivan's architecture was providing large uninterrupted floor areas and to allow ample light into the interior.

分析:the function to provide,

例:The chief goal of biochemistry is for understanding the structure and behavior of the carbon-containing compounds that make up various components of a living cell.

分析:the chief goal is to understand

(5) 其他同根名词

ability to do 受到be able to 的影响

attempt to do 企图

decision to do 决定, 受decide的影响

ambition,

be ambitious to do

effort

例:For ancient people, myths were often attempts explanation

以上就是小编给大家分享的四级备考要点,希望可以给大家学习带来帮助。