主语从句语法详解大全
如何区分主语从句，和定语从句？
如何区分主语从句，和定语从句？
定语从句在句中做定语，修饰一个名词或代词，被修饰的名词，词组或代词即先行词。定语从句通常出现在先行词之后，由关系词引出。 关系代词:who,whom,whose,which,that. (这是定语从句引导词) 关系副词:when,where,why. (这是状语从句引导词) 主语从句是在主语语法空位上填一个名词性成分(由wh-，that引导的句子),构成一个主语从句。 (It) is good.中的It是主语，你可以用一个由wh-，that引导的句子来替换It，构成一个主语从句。 如:(What I like) is good.我喜欢的东西是好的 懂了吗
how引导主语从句作什么成分？
你说了主语从句，那就是做主语了，因为从句是根据它充当的成分来命名的，比如做主语叫主语从句，做宾语成分就叫宾语从句
主语从句引导词及用法总结？
that引导。
例句：That you are coming to London is the best news I have heard this long time.你将来伦敦是好久以来我听到的最好消息。
引导主语从句的连词that有时可省，有时不能省，其原则是：若that引导的主语从句直接位于句首，则that不能省略;若that引导的主语从句位于句末，而在句首使用了形式主语it，则that可以省略
主语从句用法归纳表格？
如：
- What we need is enough time.
这句话中 What we need 就是主语，是一个句子
?由引导词引导，放句首
- That she was chosen made a tremendous stir in her village.
- Why the woman was murdered is still a question.
- Whether it will do us harm remains to be seen.
那所谓的主语从句呢，就是把原来由一个词充当的主语变成了一个完整的句子，这个句子在这句话里跟一个名词起的作用是一样一样的
举例：
- What we need is enough time.
这句话中 What we need 就是主语，是一个句子
?由引导词引导，放句首
- That she was chosen made a tremendous stir in her village.
- Why the woman was murdered is still a question.
- Whether it will do us harm remains to be seen.
?it作形式主语，代替主语从句放句首，主语从句放句末
举两颗栗子
- Where you came from doesn#39t make any difference.
- It doesn#39t make any difference where you came from.
- Whether it will do us harm remains to be seen.
- It remains to be seen whether it will do us harm.
上面的两组句子，其实是一个意思，只是位置发生了变化，一个在前一个在后
主语从句通常由这些词进行引导： that、whether、what、who、whom、which、whose、when、where、why、how等。
，无词义，看见了就当没看见一个样
that引导主语从句的两种情况
?that 从句在句首
- That you are coming to London is a good news to us．
- That the seas are being overfished has been known for years.
注意：这是 that 存在感最强的时候了，当“头儿”了，所以不能省略
?that 从句在句末
用先行词it作形式主语，that引导的主语从句放句末的情况常见于以下4种
① It be 形容词 that从句
常见的结构如下：
- It is clear that 显然...
- It is possible that 很可能...
- It is likely that 很可能...
- It is natural that 很自然...
- It is certain that 可以相信...
- It is strange that 奇怪的是...
- It is fortunate that 幸运的是...
- It is necessary that 有必要...
?It#39s necessary that we should make full preparation for the exam.
?It’s strange that it hasn’t been noticed before.
② It be 名词 that从句
常见的结构如下：
- It is a pity that 可惜的是…
- It is a fact that 事实是…
- It is a good news that …真是太好了
- It is a good thing that …真是件好事
- It is no wonder that 难怪…
- It is a shame that 遗憾的是…
- It is an honor that 真荣幸…
- It is a common knowledge that …是常识
- It is a miracle that …真是奇迹
?It is a good news that she finally lives in her home city.
?It’s a wonder that he is still alive.