一 名词性从句:
1. 主要包括主语从句,宾语从句,表语从句和同位语从句. 一般由that 引起,也可由who, what, when, why, which, whom, whether, how 引起.
2. 主语从句很多情况下都可以放到句子后面,而用代词it作形式上的主语. :
3. 形式宾语
4. 由名词性关系代词whatever, whoever, whichever 等引起的宾语从句
5. whether and if 都能引导从句, 但用法有所不同. 当主语从句直接位于句首时,应用whether,而不用if. Whether 后能直接or not, 但if 不能.
Whether he will come or not is not known.
6. 在名词reason后的表语从句必须用that引导, 不可误用 because.
The reason why he is often late for class is that he has the bad habit of getting up late in the morning.
二: 定语从句
1. 引导定语从句的关系词有who, whom, whose, that, when, where, why and which. 在非限制定语从句中, 只可用which, who, whose, where , when., 如果指代前面整个句子, 多用which.
2. 当引导定语从句的先行词前有all, any, no, little, much, very first 等词, 或先行词前为形容词最高级所修饰时,或先行词为all, anything, nothing, something, everything 时,从句的引导词只能用that.
3. as 可做引导词引导定语从句, 多和such, the same 连用. As 引导的定语从句也可修饰整个句子, 既可放在先行词后,也可放在句子开头.
4. 介词+which/whom/whose从句
5. 代/名+介词+which 从句
6. 同位语从句和定语从句
三 状语从句:
修饰主句中的动词, 形容词和副词, 通常有从属连词引导, 按其意义和作用可分为时间, 地点, 条件, 原因, 让步, 目的, 结果, 方式, 比较.等
1. 时间状语从句:
1) 常见连词有 after, as, before, once, since, till, (not)until, when, whenever(no matter when), while, as long as, as soon as etc.
2) no sooner…than, hardly(scarcely, barely)…when: 刚做…就….
3) 还有 immediately, directly, instantly, the moment, the minute, the instant, the second, every time etc
2. 地点状语从句: 一般用where or wherever 引导
3. 条件状语从句:真实条件从句:if, unless, so long as, provided that, supposing that, on condition that, in the event that, in case that etc
4. 原因状语从句: 从属连词有because, as ,since, for, now, that, in that, seeing that, considering that(鉴于,由于)
5. 让步状语从句:
1): even if, though, even though, while(尽管) no matter what/how/which, however, whatever, whichever, however etc.
2) 由as 引起的让步从句, 语气较强烈,被强调的词须放在句首.
3) whether…or,不管…或…
6. 结果状语从句: so that, so…that, such…that
7. 目的状语从句: so that, in order that, for fear that, lest, in case
8. 方式状语从句: as, just as, as if: 如同…一样
9. 比较状语从句:
1) as…as, not so/as…as
2) 比较级+than, so much/a lot more than
3) no more…than, not more…than, less…than
4) the more…the more
从句是相对于主句而言的,即它是从属于某一个主句,而不能单独作一个句子。在英语中,主要有三大从句,即名词性从句(包括主语从句,宾语从句,表语从句,同位语从句)、形容词性从句(即定语从句)、副词性从句(即状语从句,包括时间、条件、结果、目的、原因、让步、地点、方式等)。
主语从句用作主语,如::
That the earth is round is true. 地球为圆的是真实的。
宾语从句用作宾语。如:
Do you know where he lives?
表语从句用作表语,如:
My opinion is that you should not go alone. 我的意见是你不应单独前往。
同位语从句用于解释说明前面的名词。如:
The fact that the earth is round is true. 地球是圆的的事实是真实的。(that从句用于解释说明the fact)
定语从句相当于一个形容词,用于修饰前面的名词。如:
The student who answered the question was John. 回答问题的学生是John.
状语从句相当于一个副词,如:
When it rains, I usually go to school by bus. 天下雨时,我通常坐公共汽车上学。(时间状语)
If he comes tomorrow, you will see him. 如果他明天来,你就可以看见他。(if 引导的条件状语从句,其结构为:if +状语从句,+主句)。要注意在状语从句中有一个规则是“主将从现”,即主句是将来时,则从句要用一般现在时表示将来。
主句和从句的划分方法是相同的。句子的成分从谓语动词处来划分比较容易。谓语动词前面的部分是主语,后面常接宾语,修饰谓语动词的是状语,修饰主语、宾语的是定语,若谓语是系动词,则系动词后的部分是表语。如:
I am a teacher. 其中,I 是主语,am是谓语,a teacher 是表语。
He likes playing football very mucy. 其中,he是主语,likes是谓语,playing football是宾语,very much是状语。
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