一、非谓语动词
“非谓语动词”可分为动词不定式、动名词和分词。它在句子中的作用很多：除了不作谓语外，它可以充当主语、宾语、表语、定语、状语与复合宾语(主语补语或宾语补语)。有些及物动词后面接不带to的不定式作复合宾语。这些动词归纳如下：一感(feel)．二听(hear，listen to)，三让(have，1et， make)，四看(see，watCh，notice，observe)。再加上help somebody(to)do something和美国英语look at somebody do somthing。还有“二让”属特殊：get somebody to do something 与keep somebody doing。而有些及物动词后面接动名词(the -ing form)作宾语。这些动词归纳为一句话：Papa C makes friends。这是由如下动词的开头字母组成：permit，advise， practise，avoid,consider,mind, allow,keep,enjoy,suggest, finish，risk，imagine,escape,need，delay，stand(忍受)。 为了容易记住，也可以编成顺口溜：“允许完成练习，建议避免冒险，考虑延期逃跑，喜欢保持想象，需要反对忍受”。其相对应的动词依次是：permit/allow,finish,practise；
advise／suggest， avoid，risk： consider， delay， escape／miss； enjoy／appreciate， keep， imagine； need/want／require,mind． can't help／can’t stand。
二、复合句
1、学生最容易混淆的是定语从句与同位语从句的区别。
例如：A、The news that our team has won the match is true． (同位语从句)
B、The news that he told us surprised everybody here． (定语从句)
关键的区别在于连接或关系代词that：有意义的是定语， 无意义的是同位。因为引导定语从句的that在从句中作主语或 宾语，而引导同位语从句的that只起到连接词的作用。
2、接着容易混淆的是引导定语从句的关系代词that与 which：that之前是不定(代词)、序数(词)、(形容词)最高级：which之前是介词短语与逗号(非限制性)。
例如：A、All that we have to do is to practise every day．
B、The first lesson that I learned will never be forgotten．
C、I have lost my pen，which I like very much.
D、The house in front of which there is a garden is my home．
三、It的用法
1、It除了代替人和物以外，还可以作形式主语。而真正的主语(不定式、动名词或从句)则放于谓语或表语之后。
例如：It is nor easy to finish the work in two days.
然而有少数表语之后接动名词作真正的主语。这些表语是：无助(no help)、无用(no use)、没好处(no good)；工作(hard work)、费时(a waste of time)、又危险(a danger)。
例如：A、It is no use crying over spilt milk.
B、It is a waste of time waiting for him．
2、It还可以作形式宾语。通常下列动词后面可接it作形式宾语：2f2tcjm(find，feel,think,take,consider，judge, make)。
例如：A、He made it clear that he was not interested in this subject．
B、I think it no use arguing with him.
3、It用于强调句式。要强调句子的某一部分(主语、宾语、 状语)，可以把it当作先行词。这种句子的结构是：It is(was)+ 被强调部分+that(who)+句子的其余部分。
例如：A、It iS Professor Lin who teaches us English—(强调主语)
B、It was in Shanghai that l saw the film.—(强调状语)
C、It was in 1990 that I worked in the factory．(同上)
但要注意与定语从句的区别。
例如：D、It was 1990 when I worked in the factory．(定语从句)
在强调句式里，我们把强调结构It is(was)…that除去，句子还很完整。如例句C。而例句D就不能。
四、倒装结构
学生容易混淆的是全部倒装与部分倒装。如何区分之，编个顺口溜：副(adv.)介(prep．)提前全倒装，其它句式部分倒；否定提前倒助动，让步状语倒表语；复合句式倒主句，不
倒装的属特殊。下面举例说明：
A、Here comes the bus．(副词提前，全倒装)
B、Here he comes.(代词作主语，不倒装)
C、In front of the house lies a garden.(介词短语提前，全倒装)
D、Never shall I do this again.(否定词提前，部分倒装)
E、Young as he is ,he knows a lot.(让步状语从句，表语倒装)
F、Only when he told me did I realize what trouble he was in．(only 修饰状语，主句倒装)
G、Only he can save the patient.(only修饰主语．不倒装)
H、Not only will help be given to people,but also medical treatment will be provided.(否定词提前，部分倒装)
I、Not only he but also we like sports.(连接两个主语，不倒装)
五、虚拟语气
虚拟语气也是一个难点。所谓虚拟语气是表示说话人的愿望、假设、猜测或建议，而不表示客观存在的事实。它通过句子的谓语动词的特殊形式来表示。现归纳如下：纯假设，用虚拟，动词时态退一级：条件句，分主从，主句谓语前加would (should,could，might)；表愿望,用虚拟，wish后面接宾语(从句)：现在过去与将来，动词时态退一级：提建议，用虚拟，宾语(从句)动词用(should)do：俩建议，三要求，再加坚持与命令(suggest,advise,demand,require,request,insist,order)：It is time和eoukd rather,后接丛句用虚拟：部分主语从句中， 谓语用虚拟结构 (It is necessry /important/natural/natural/strange/strange that……should do)。 下面举例说明：
A、If you came tomorrow,we would have the metting. (条件句虚拟)
B、Without air,there would be no living things.(同上)
C、We wish we had arrived there two hours earlier.(表示愿望虚拟）
D、He demanded that we (should)start right away.(表示建议虚拟)
E、It is(high)time that we left (should leave)now．(特殊从句虚拟）
F、I would rather you gave me the book．(同上)
G、It is necessary that we should clean the room everyday，(主语从句虚拟)
H、He speaks English so fluently as if he were English． (特殊从句虚拟)
总之，语法是从语言实践中总结出来的规则，要边学边寻找规律，以提高学习效率。在学习中不能只记一些语法规则，要进行实践练习。通过练习，可以发现和纠正错误，而且有利于况固所学知识。
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