专升本英语核心语法（一）句法知识点汇总第一章：英语复合句第一节：主语从句主语从句指的是在主语的位置出现的不是词或者词组，而是一个句子，这样的句子就称为主语从句。
例如：what he said is true .That he did so much made everyone puzzled.1）引导主语从句的词有：that,whether,who,what,which,when,where,how,why 等。
例句：1.When and where we have this meeting has not beendecided .2.Whether he will come or not was not very clear .3.Who had stolen the gun has not been known .4.Which one will be our teacher is a secret .5.How we solve this problem is very serious .6.Why he didn’t kill her has not been known2)有些时候由于主语太长，可以用it作为形式主语来代替主句。
很多考生对于it作形式主语代替主语从句存在一个误区，即所有的主语从句都能用it代替，这样太绝对了，应当说that,whether 引导的主语从句都可以用it作形式主语，其余的尤其是what ,whatever,whoever引导的主语从句，基本上都不用it代替。
如：It is said that there are 300 people killed in the accident at least .据说至少有300人死于这场事故。
1.It is estimated that in some of the biggest cities of the Third World , more than half of the water entering the system is lost through leaks in pipes .据估计，在第三世界的一些大城市中，有一半以上的水由于水管漏水而流失。
2.What acts as a reinforcement for one may not foranother .对一个人来说是激励的做法，不见得合适另外一个人。
3.It is not always the case that new things are promoted because they have good impacts for the majority of people .因为对大多数人有好的影响，故而新的事物会被促进，情况并非总是这样。
4.Whether he will accept our invitation doesn’t concern you .他是否会接受我们的邀请与你无关。
5.It doesn’t matter whether they are learning Maori or German or Chinese or any other language .他们是否在学习毛利语，德语或者汉语或者其他任何语言都无关紧要6.It’s not surprising we see some effect .解析：第一句，类似表达有：It is +动词的过去分词（said,estimated, reported , believed ）+主语从句；第三句是另外一种类型：it is +名词（always the case, a fact , apity , a shame, an honor）+主语从句It is +形容词（fortunate,unlikely, obvious, necessary , strange, natural）+主语从句；第四句与第五句，应当注意whether ,if 均表示“是否”，但是if 不能放在句首，可写成：It doesn’t concern you if he will accept our invitation .第6句中把连词that 省略了， that 引导的主语从句如果放在句首不可省略，但是如果放在后面用it 做形式主语，可以省略，但是经常不省略。
Tips :在主语从句中that 作为引导词不可省略，无意义；其余引导词有意义，不可省略，疑问词引导从句时，从句用陈述句语序。
第二节：宾语从句宾语从句指在宾语的位置不出现词或者词组，而出现一个句子，成为宾语从句。
如：I suppose (that) her bag has been stolen .Henry wanted to know if she will come .引导宾语从句的词有：that, whether, if, who, whom , whose, which, when, where, how, why .如：Everyone doesn’t know where it is .Henry wants to know when Bruce will comeSherry is studying how to use this machineTips: 注意这是代词+不定式作宾语从句的现象。
The teacher asked me why I was late .Bruce showed which one is better .Let’s see whose shirt it is .I know who did itTips:宾语从句中的that 作为引导词可省略，无意义；其余引导词有意义，不可省略，疑问词引导从句时，从句用陈述句语序。
如：I think (that )we will land on the moon one day .1.They and the other monkeys must be followed stilllonger , however , to know whether low-calorie intake can increase both average and maximum lifespans inmonkeys .要对他们和其他的猴子观察的时间更长一些，才能确定是否低卡路里摄入量能延长猴子的平均寿命也能增加他们寿命的上限。
2 . I was wondering if you could give me someinformation about membership and facilities .我想知道你是否可以给我提供一些关于会员以及设施的问题3.Please note that provisional bookings from overseas visitors will be held for 14 days .请注意海外临时预订可以保留14天。
4.He is clear that the present situation will not last long .他很清楚目前的情形不会持续很久。
5. It focused on what would be most appropriate for the inhabitants .它重点关注什么是最适合当地居民的。
分析：：放在动词后，介词后，形容词后。
第三节：表语从句表语从句指在表语的位置不出现词或者词组，而是句子。
如：That is why he was late .It’s how we solve this problem引导表语从句的词有：that, whether , if, who, what , which, when, where, how, why .例：The difficulty is that we couldn’t speak FrenchThe question is whether (if) they will come .The problem is who will take over this subject .That is what we are anxious to .The suggestion is which one go to American is better .The last question is when and where we hold the competition .The problem is how to solve the affair .Tips :表语从句中that 作为引导词时不可省略；无意义；其余引导词有意义，不可省略，疑问词引导表语从句时，从句用陈述句语序。
和表语位置一样，表语从句放在系动词（be, seem,look, appear….）后。
如果表语从句是that 引导的，在口语中有时候是可以省略的，在正式句子中最好别省略。
经典例句：1.One encouragement is that the results of similarstudies about other environmental issues suggest thatolder children seem to acquire the ability toappreciate , value and evaluate conflicting views .令人鼓舞的是，关于其他环境问题的类似研究的结果表明，大一点的孩子似乎能获得重视，评价和评估相冲突的观点的能力。
2.The reason is that nobody associated the reactionprinciple with the idea of travelling through space to a neighboring world .原因在于没人把反作用原理与漫步太空到相邻的世界联系在一起。
3.The main difference between a tree and a building is atree has got an internal mechanism to keep thepemterature regulated .一棵树和一栋建筑的主要不同是树有内在机制去调节温度。
4.It appears that the sediment-free water emerging fromthe Aswan dams picks up silt and sand .看来，从阿斯旺大坝流出的不含沉淀物的河水能卷起淤泥和沙石。