2020届高三二轮复习：第4讲 状语从句

第四讲状语从句

一、明备考方向

二、攻重点难点

(一)引导时间状语从句的从属连词及重点句式

1．引导时间状语从句的从属连词有：when, whenever, while, as, before, after, since, till/until, as soon as, no sooner ...than, hardly/scarcely ...when, immediately, instantly, the moment, every/each time等。

2．在掌握时间状语从句时，要注意以下几个重点句式：

(1)not ...until ...“直到……才……”

(2)It＋will be/was＋一段时间＋before ... “过……(时间)才……”

(3)It＋is/has been＋一段时间＋since ... “自从……以来多长时间了”

(4)It＋was＋not long before ...“不久……就……”

(5)No sooner＋had＋主语＋过去分词 ...than ...(正常语序：主语＋had no sooner＋过去分词＋than ...) “一……就……”

(6)Hardly/Scarcely＋had＋主语＋过去分词 ...when ... (正常语序：主语＋had hardly/scarcely ＋过去分词＋when ...)“一……就……”

When I lived there, I used to go to the seashore on Sundays.

我住在那里时，星期天常到海滨去。

Please don't talk so loud while others are working.

在别人工作的时候，请别这么大声音说话。

It was some time before I realized the truth.

过了很长一段时间我才悟出真相。

He had no sooner finished his speech than the students started cheering.

＝No sooner had he finished his speech than the students started cheering.

他刚完成演讲学生们就开始欢呼起来。

(二)引导条件状语从句的从属连词的用法

引导条件状语从句的从属连词有：if, unless(除非), as long as/so long as(只要), in case(以防，万一), only if(要是……就好了), on condition that, providing/provided (that),

suppose/supposing (that)等。

1．if和unless引导的条件状语从句。if表示正面的条件，意为“如果”；unless(＝if ...not)表示反面的条件，意为“除非，如果不”。

If we go on polluting the environment, the earth won't be fit for us to live in.

如果我们继续污染环境，地球将不再适合我们居住。

You'll fail the exam unless you study hard(＝if you don't study hard)．

除非你努力学习，否则你考试会不及格。

2．in case, on condition that, providing (that), provided (that), supposing (that), suppose (that)等词汇意思相近，意为“万一，假使，假如，在……条件下”。

In case there is a fire, what will we do first?

万一发生火灾，我们首先要做什么？

Suppose/Supposing (that) they refuse us, who else can we turn to for help?

假如他们拒绝了我们，我们还能求助于谁？

They agreed to lend us the car on condition that we returned it before the weekend.

他们同意把车借给我们，条件是我们在周末前归还。

3．as long as(＝so long as)引导语气强烈的条件状语从句，意为“只要”。

As long as you don't lose heart, you will succeed.

只要你不灰心，就会成功。

(三)引导原因状语从句的从属连词的用法

引导原因状语从句的从属连词有：because, as, since(既然，因为)，now (that)(既然), seeing (that), in that等。

1．because语气最强，表示必然的因果关系，用来回答why的提问；

2．since语气稍弱，表示对方已知的原因或事实，意为“既然；因为；由于”，相当于now (that)；

3．as语气最弱，往往不是明显的原因，只是对结果的附带说明。

I was absent from the meeting because I was ill.

因为我病了，所以我缺席了这次会议。

As it is raining, we shall not go to the park.

由于在下雨，我们不去公园了。

Now (that)/Since everybody is here, let's begin our meeting.既然大家都在这里，我们开始开会吧。

(四)引导让步状语从句的从属连词的用法

引导让步状语从句的从属连词有：although, though, as, even if/though(尽管，即使), while(然而), whether ... or (not), however, whatever, whoever, no matter how/what/who等。

1．although/though(尽管，虽然), even if/though(即使)引导的让步状语从句