英语从句的语法学习详解
从句是英语语法的重要组成部分，也是我们学好英语的过关知识，以下是小编为大家整理的关于从句的语法详解，希望能帮到你。
宾语从句三类的用法详解
宾语从句可以分为三类
学习啦在线学习网 (1).动词的宾语从句
学习啦在线学习网 1.1 大多数位于动词后面
Eg：I hope you can join us in the game.
学习啦在线学习网 1.2 有些是“动词+副词”后
学习啦在线学习网 Find out / point out / figure out / turn out/ figure out
Eg： Can you figure out what the poet really means in this poem?
学习啦在线学习网 1.3 有些动词短语后面
学习啦在线学习网 Make sure / make up one’s mind / keep in mind
学习啦在线学习网 Eg; we should keep in mind that sports can be a great boost to our health.
(2) it 作形式宾语代替宾语从句
第一类动词; find/ feel/ think/ consider/ make / believe/ guess/ suppose /assume等后面有宾语不足语时，需要用it 作形式宾语而将that引导的真正的宾语从句后置。
Eg： I think it necessary that we do some sporting.
第二类动词 带宾语从句时需要在从句前面加it。
学习啦在线学习网 这类词：hate / like/ dislike/ appreciate/ depend on/ see to /
Eg: I hate it when they talk without considering other’s feeling.
学习啦在线学习网 但是如果宾语从句是WH-类引导的，其后面有to be 短语作宾语补足语，不可以用it 代替。
学习啦在线学习网 We all consider what you said to be unbelievable. (right)
学习啦在线学习网 We all consider it to be unbelievable what you said .(wrong)
学习啦在线学习网 (3) 形容词后的宾语从句
Adj: sure / certain/ glad/ pleased/ happy / afraid / sorry 等等。
Eg; I am not sure whether you will come or not.
引导状语从句的连词讲解
从属连词
从属连词是引导状语从句，宾语从句及其他从句的连词。
学习啦在线学习网 1.引导状语从句的从属连词有：
学习啦在线学习网 1)when, while, before, after, as soon as, until, since等，引导时间状语从句。
2)because, as, since等引导原因状语从句。
学习啦在线学习网 3)if, as long as等引导条件状语从句。
4)though, although引导让步状语从句。
5)so…that…, such…that…等引导结果状语从句。
6)so that引导目的状语从句。
7)as?as?;than等引导比较状语从句。
学习啦在线学习网 2.常用从属连词的辨析
1)when, as, while
when, as, while都表示“当…的时候”，但when引导的时间状语从句的动作和主句的动作可以是同时发生，也可以先后发生，when既可指时间点，也可指一段时间，所以既可引导一短暂动作动词，也可引导持续性动作的动词。
学习啦在线学习网 用as作从属连词引导时间状语时强调主句和从句的动作并行发生，不指先后，尤指短动作或事件同时发生。如：As I looked, someone came near.(正当我看的时候，有个人走上前来。)as还可说咱两种正发展或变化的情况，意为“随着”。如：As spring warms the earth, all flowers begin to bloom.(随着春回大地，百花开始绽放。)表示主从句动作同时，as意为“一边…一边…”。如：He hurried home, looking behind as he went.(他匆匆忙忙跑回家，一边走一边回头望。)
分词或分词短语作状语用法
学习啦在线学习网 ㈠ 分词或分词短语作状语时，可以表示
学习啦在线学习网 时间、原因、条件、让步(可转换成相应的状语从句)
学习啦在线学习网 ① Put into use in April 2000, the hotline was meant for residents reporting water and heating supply breakdowns.
Put into use in April 2000 == When it was put into use in April 2000(时间状语)
学习啦在线学习网 ② Blamed for the breakdown of the school computer network, Alice was in low spirits.
Blamed for the breakdown of the school computer network
== Because she was blamed for the breakdown of the school computer network(原因状语)
③ Given time, he'll make a fist-class tennis player.(条件状语)
学习啦在线学习网 Given time == If he is given time
④ Left at home, John didn't feel afraid at all.
学习啦在线学习网 Left at home == Although he was left (让步状语)
学习啦在线学习网 表示方式，伴随状况或结果(可以转换成并列句或非限制性定语从句)
① We often provide our children with toys, footballs or basketballs, thinking that all children like these things.
thinking that all children like these things.== and think that all children like these things.(伴随状语)
学习啦在线学习网 ② He earns a living driving a truck.
学习啦在线学习网 driving a truck == by driving a truck. (方式状语)高考对分词用作方式状语考得
学习啦在线学习网 ③ He fired, killing one of the passers-by.
学习啦在线学习网 He fired and killed one of the passers-by. (结果状语)
学习啦在线学习网 ④ He died, leaving his wife with five children.
He died and left his wife with five children. (结果状语)
⑤ It rained and rained, vehicles bogged and bridges washed out.
It rained and rained, and vehicles were bogged and bridges were washed out. (结果状语)
㈡ 有时为了强调，分词前会加when, while, if, unless, once, though, even if, as if 等连词一起作状语
When comparing different cultures, we often pay attention only to the differences.
学习啦在线学习网 Though tired, he still continued reading.
学习啦在线学习网 Once published， this book will be popular with the students.
学习啦在线学习网 ㈢ 分词(短语) 与主语的关系
主语一致：分词短语的动作由主句主语发出。看以下错误
学习啦在线学习网 Waiting for the bus, a brick fell on my head.
Hearing the news, tears came into his eyes.
Finding her car stolen, a policeman was asked to help.
学习啦在线学习网 When using the computer, the password must be remembered.
有自己主语的分词结构— 独立分词结构。分词有自己意义上的主语，分词的动作不由主句主语发出。
学习啦在线学习网 The town seen from the hill，we can see it more clearly
.=If the town is seen from the hill，we can see it more clearly. 如果从山上看这座城市，我们能看得更清楚。
学习啦在线学习网 Everything taken into consideration，the party was a success. 将所有的事情考虑在内，晚会算是成功的。
学习啦在线学习网 while只指一段时间，从句中的谓语动词不能用终止性动词，强调某一段时间内主从句动作同时发生，常对同类的动作进行对比。如：While we were waiting for a bus, it was raining hearily.(我们在等车时，天正下着大雨。)
2)till和until
till和until都表示“直到…为止”。主句用延续性动词，主句和从句都用肯定式：意为“直到…才”。主句用终止性动词，从句用肯定式，主句用否定式。until较till正式，until引导的时间从句可以放在句首。
例如：
She won't go away till you promise to help her.
学习啦在线学习网 直到你允诺要帮助她，她才走开。
学习啦在线学习网 Until you told me, I had heard of nothing what happened.
学习啦在线学习网 直到你告诉我，我才知道发生了什么事。
3)since
学习啦在线学习网 since引导的时间状语从句常用一般过去时，其主句一般使用现在完成时。
例如：
Jim has been in the factory for two years since he left school.
学习啦在线学习网 从吉姆毕业起，他在这家工厂工作两年了。