从句what和how的用法与区别

从句what和how的用法与区别
what 和how的用法比较
what讲解
what = all that/ the thing that/ the person that. 只引导主从，宾从，表从，不能引导定从和同位从，即what前面不能有名词。

既起连接作用，又在从句中充当主、宾、表语的成分。

即：what+不完整句子，做主从，宾从，表从。

例：What he said made me happy.（主从）what引导主语从句，在从句中作宾语。

1. what引导主语从句的特点：a.前面没有东西；b.后面有两个动词。

I thought the movie would be good for my English, but 76 it turned out, it was an Italian movie.
A）since B）when C）what D）as
解析答案为D。

2.what引导宾从和表从。

公式：动词/介词/系词+that+不完整句子
I know what he said. （宾从）what引导宾从，在从句中作宾语。

I listen to what he said.（宾从）what引导宾从，在从句中作宾语。

This is what he said. （表从）what引导表从，在从句中作宾语。

例：You 80 the clock with the latest time at 81 you want to be wakened…
81. A) where B) this C) which D) that
解析答案为C。

For starters, cabin pressures at high altitudes are set at roughly 81 they would be if you lived at 5,000 to 8,000 feet above sea level.
A) who B) what C) which D) that
解析答案为B。

who在从句中一般做主语，只有在非正式时做宾语。

优先原则：however > whether > what
…but a bird has a single alarm cry, 75 means “danger!”
A）this B）that C）which D）it
解析答案为C。

做题时，排除其他选项只剩which和that时，有逗号的选which,没逗号的一般选that。

The word geography 74 from two Greek words, ge, the Greek word for “earth” and graphein, 75 means “to write”.
75. A）what B）that C）which D）it
解析答案为C。

Before you buy an expensive 84 , or a service, do check the price and 85 is on offer. 85. A) what B) which C) that D) this
解析答案为A。

what与how的区别
what连接代词，必须代替从句中的主/宾/表语。

例：I don’t know what to do.
how连接副词，必须代替从句中的方式状语。

例：I don’t know how to do it.
We started thinking of to do about it.
A) what B) how C) whether D) when
解析答案为A。

It caused them to think about 84 they might control the experiences of children…A）what B）how C）whatever D however
解析答案为B。

how在从句中作方式状语。