初中英语语法：状语从句

状语从句

Adverbial clause

状语：修饰动词、形容词、副词或整个句子，通常由副词、介词短 语、动词不定式、分词、从句等充当。状语的位置比较灵活，可以位于句首、句末或句中。

Obviously, our grandparents were pleased to get our phone call.

显然，我们的爷爷、奶奶很愿意接我们的电话。（副词）

We worked hard, from sunrise to sunset. 我们努力工作，日出而作，日落而息。（介词短语）

To help my disabled aunt, I spend an hour working in her house every day.

为了帮助我残疾的姑妈，我每天花上一个小时在她家里帮忙。（不定式）

Seen from a distance, the farmhouse looked deserted. 从远处看，这座农舍似乎是荒废的。（过去分词）

It rained heavily, causing severe flooding in that city. 大雨滂沱，造成了那个城市洪水泛滥。（现在分词）

I know how to light a camp fire because I had done it before.

我知道如何生篝火，因为以前我做过。（原因状语从句）

状语从句：指用作状语、起副词作用的句子。它可以修饰谓语、非谓语动词、定语、状语或整个句子。状语从句一般由连词（从属连词）引导，也可以由词组引起。从句位于句首或句中时 通常用逗号与主句隔开，位于句尾时可以不用逗号隔开。

He is absent today, because he is ill.

他今天缺席，因为他病了。

Where there is a will, there is a way.

有志者，事竟成。

另外，状语从句有时放在主语和动词之间，造成分隔现象。Anyone, no matter who, may point out our shortcoming.

任何人，不管是谁，都可能会指出我们的不足之处。（主语anyone与动词may point out被状语从句no matter who分隔）

一、状语从句常见引导词

根据其作用可分为时间、地点、原因、条件、目的、结果、让步、 方式和比较等从句。常用引导词如下表：

时间状语从句

连词 :as/when/while;after;before;since;once;till/until;

whenever;no sooner...than.../hardly...when...

副词：immediately;directly

名词短语：the monment;the minute;by the time;next time

条件状语从句 if;unless;as/so long as;on condition that;suppose/supposed that;

provided/providing that;in the event that

原因状语从句 because;as;since;now(that)

结果状语从句 so/such...that...

目的状语从句 so that;in order that;in case

让步状语从句 though;although;as;however;no matter...;疑问词+ever...;whether...or not...

比较状语从句 than;as/so...as;the more...the more..

方式状语从句 as;as if;as though

地点状语从句 where ;wherever

二、一些引导词的用法

1、when的用法

（1）when表示时间点和时间段。有时同as soon as/immediately/instantly/directly等词的意思。

when用于固定结构“hardly/scarcely... when...”，此时when 可换作before。

注意：当把 hardly/scarcely放句首时，句子需部分倒装。

We will start when the monitor comes.

班长一来，我们就出发。

I had hardly arrived home last night when it began to rain.=Hardly had I arrived home last night when it began to rain.

昨晚我一到家，就开始下雨了。

（2）when 有时可译为“如果……”，相当于if，引导条件状语从 句。

Smog will be distant from us when everyone fights against pollution.

如果人人反对污染，雾霾就会远离我们。

（3）when可作并列连词，引导并列分句，意为“突然……”或“这时……”，表示一个动作“正在发生”“即将发生”“刚刚完成”时突然插入另 一个动作。when相当于and just time或and just at that time,常用于下列三种句型：was/were doing... when...; was/were about to do（on the point of doing）... when...; had done... when...

例如：

I was walking along the river when I heard a drowning boy crying for help.

我正沿着河边走，突然听到一个溺水儿童的呼救。

I was about to go out when an unexpected visitor came.

我正要出门，一位不速之客来访了。

We had just planted 100 trees when it began to rain.

我们刚刚栽完100棵树，就开始下雨了。

2、while的用法 while表示时间段，作并列连词，表示前后对比。while引导的让步 状语从句多放在句首，相当于although，表示“尽管，虽然”。

There’s plenty of rain in the southeast, while there’s little in the northeast.

东南部雨量充足，而东北部则很少下雨。

While I understand what you say, I can’t agree with you.

虽然我理解你的意思，但我还是不能赞同你。

注意：

①when引导的时间状语从句既可放在句首，也可放在句末；而while引导的让步状语从句一般放在句首，不放在句末；另外，也可以从意义上加以区分。

②while和when都可以引导时间状语从句，但应注意：while 引导的时间状语从句中的谓语动词必须是延续性的动词；而when 引导的时间状语从句中的谓语动词既可以是延续性动词，也可以是非延续性动词。当时间状语从句中的谓语动词是延续性动词时，while和when可以互相替换。

例如：

The bus had left when we arrived at the bus stop.

当我们到达车站时，公共汽车已经开走了。（arrive是非延续性动词，因此，此句中的when不能用while替换）

When/While we were having a meeting, our teacher came in.

我们正在开会时，老师走了进来。（have是延续性动词，因此，句中的when可以用while替换）

③ while引导的状语从句还可以表示“某个动作正在进行的同时，另一个动作也在进行之中”。

例如：

While the teacher was speaking, the students were listening.

老师在讲课，学生们在听。

3、 as的用法

（1）as与when, while都是引导时间状语从句的从属连词，含义都 是“当……的时候”。as意为at the same time that“正当……；与……同 时”，它兼指“时间点”和“时间段”，从句的动词既可是延续性动词，也 可是非延续性动词，意为“一边……一边……”，“随着”。

The door bell rang as we were having breakfast.

正当我们吃早饭的时候，门铃响了。

As the time went on（=With the time going on）, the weather got worse and worse.

随着时间的推移，天气越来越糟。

（2）while意为during the time that“在……期间”，指一个“时间 段”，不能表达“时间点”，从句的动词只限于延续性动词；when意为at the time that“在……时”，多指“时间点”。

Strike while the iron is hot. 趁热打铁。

It was snowing when he arrived at the construction site.

他到达工地时正在下雪。

（3）as可以引导让步状语从句。as与although（或though），however（或no matter how）等都可以引导让步状语从句，含义是“虽 然，尽管”，但它们有区别：although语气稍正式些，可放在句首，也可 放在句中，主句中不能再用but，但可以用yet；as所表达的语气较强，引导的让步状语从句用倒装语序；however引导让步状语从句时，它的后面可跟形容词或副词，也要用倒装语序。

Strange as it may seem, nobody was injured in the accident.

这次意外虽然很奇怪，却没有人受伤。

Young as he is, he knows everything.

尽管小，他什么都知道。还可表达为：

Though he is young, he knows everything. Young though he is, he knows everything.

Although he is young, he knows everything. However young he is, he knows everything.

另外，though还可以作为副词，意为“可是，然而，不过；话虽这样说”，一般位于句尾。

I wish you had told me, though.

不过，我希望你曾告诉过我。

He said he would come, he didn’t, though.

他说他要来，可是他并没有来。

另外，as还可以引导原因状语从句。

As rain has fallen, the air is cooler.

因为下过雨，空气比较清爽。

4、 so/such... that... 均可引导结果状语从句

该句型中的such是形容词，修饰名词；so是副词，修饰形容词或副词，具体的搭配形式是：“so+adj./adv.+that”，“so+adj.（+a/an） +n.+that”；“such（+a/an）（+adj.）+n.+that”。

He speaks so fast that no one can catch him.

他说话太快，无人听得明白。

He’s such a good person that we mustn’t blame him.

他是这么好的人，我们千万不要怪他。

There is so rapid an increase（=such a rapid increase）in population that a food shortage is caused.

人口增长如此迅速，以致造成了粮食短缺。

They are such fine teachers that we all hold them in great respect.

他们是非常好的老师，我们对他们极为尊敬。

It is such nice weather that I would like to go to the beach.

天气如此好，我想去海滩。

The country has so much coal that it can export large quantities.

那个国家的煤炭非常丰富，可以大量出口。（so与表示数量的代词many, few, much, little等连用已经形成固定搭配，不能换用such）

三、状语从句的时态和语气

状语从句主句和从句的时态要保持一致。注意下列情况：

1、“主将从现”的原则

在时间状语从句和条件状语从句中，主句是一般将来时/祈使句/含 有情态动词原形，从句要使用一般现在时态。但will在表示意愿时，可用于上述状语从句。

I’ll tell him the good news as soon as he comes back tomorrow.

他明天一回来我就会告诉他这个好消息。

Go on until you reach the bridge.

继续前行，直至你走到桥边。

If you work hard, you can pass the examination.

如果你努力学习，你就能通过考试。

If you will wait, I’ll go and ask the manager.

如果你愿意等，我就去问问经理。

2、No sooner... than.../hardly（scarcely）... when... 句型的时态问题

No sooner... than.../hardly（scarcely）... when...表示“一……， 就……”，引导时间状语从句，主句须用过去完成时，从句用一般过去时。No sooner/hardly（scarcely）位于句首时，主句需倒装。

He had no sooner been there than I told him about it.

他一来，我就告诉他了。

No sooner had he been here than I told him about it.

他一来，我就告诉他了。

3、as if（though）引导的方式状语从句的时态和语气问题

as if（though）引导方式状语从句，若所述情况可能性小，谓语动词用虚拟语气，时态在原基础上向过去退一步。若从句所述情况可能实现，则用陈述语气。

He speaks to me loudly as if I were deaf.

他大声冲我说话，好像我是个聋子。（实际不是）

It is blowing hard as if it is going to rain.

风很大，好像要下雨了。（真要下雨）

4、if引导的条件状语从句的时态和语气问题

if引导的条件状语从句，表示在某种条件下某事很可能发生。if还可以引导虚拟条件句，表示不可实现的条件，从句中多用一般过去时或过去完成时。

If I had enough money, I should（would）buy the car.

如果我有足够的钱，我就会买下这辆车。（事实上现在钱不够）

If I had got up earlier I should（would）have met her.

如果我起床早一些的话，我就会遇见她了。（事实上我起床晚了）

If he would come here tomorrow, I should（would）talk to him.

如果他明天来这里的话，我就会和他谈一谈。（事实上他明天来的可能性极小）

四、状语从句的省略

状语从句同时具备下列两个条件：

①主句和从句的主语一致，或从句主语为it；②从句主要动词是be的某种形式，从句中的主语和be动词常可省略，这样使得语言更加简洁明了。状语从句的省略常包含如下结构：

（1）连词+名词。

He acts as if（he is）a fool.

他表现得就好像是个傻子一样。

（2）连词+形容词。

You must attend the meeting unless（it is）inconvenient to you.

除非情况对你来说不方便,否则你必须出席这次会议。

Work hard when（you are）young, or you’ll regret.

趁年轻要努力学习，要不然你会后悔的。

（3）连词+现在分词。

He fell asleep while（he was）doing his homework.

他在做作业的时候睡着了。

（4）连词+过去分词。

If（it was）untreated, it would produce a powerful poison that would kill the patient.

如果不处理它，它将产生一种导致该病人死亡的烈性毒物。

Though（they were）tired, they went on working.

虽然他们累了，但他们仍继续工作。

（5）连词+介词短语。

While（I was）at college, I began to know him, a strange but able student.

我上大学时开始认识他的，他是一个奇怪但有能力的学生。

（6）连词+不定式。

The patient opened his mouth as if（he was）to speak.

病人张开嘴巴好像要说什么。

You shouldn’t come to his party unless（you were）invited.

除非你被邀请，否则你不应该来参加他的派对。

五、状语从句和状语的相互转换

1、.状语从句转换为分词短语

状语从句主句和从句一致时，转换为分词短语。

After he turned off the TV, he went out of the room. →Having turned off the TV, he went out of the room.

他关闭电视机后走出了房间。

When the city is seen from the mountain, it looks much more beautiful. →Seen from the mountain, the city looks much more beautiful.

从山上看，这座城市看起来更漂亮。

2、状语从句转换为独立主格结构

状语从句主句和从句不一致，转换为独立主格结构。

If weather permits, we’ll have the meeting in the open air. →（With）Weather permitting, we’ll have the meeting in the open air.

如果天气允许，我们将在室外召开这次会议。

3、状语从句转换为介词短语

由after/before/since/as soon as等引导的时间状语从句，可改为 after/before/since/on+动名

词短语结构。当主从句主语一致时，可使用动名词的复合结构。

Before he dived into the lake, he made a deep breath. →Before diving into the lake, he made a deep breath.

在跳入湖中之前，他深深地吸了一口气。

可以用来代替状语从句的常见介词短语有：because of/at the age of/in spite of/as a result o等。

He is absent today because he is ill →He is absent today because of illness.

他今天缺席是因为生病了。

4、状语从句转换为动词不定式短语

状语从句还可以根据情况转换为不定式短语。

He is so strong that he can lift the heavy stone.→He is strong enough to lift the heavy stone.

他很强壮，足以搬动这块重石。

He was so weak that he couldn’t go a step further. →He was too weak to go a step further.

他太虚弱了，无法再挪动一步。

He stood in the front of the classroom in order that he could see the picture clearly. →He stood in the front of the classroom in order to（so as to/to）see the picture clearly.

他站在教室前面，以便能清楚地看到图片。

注意主语和状语的逻辑主语要保持一致性。下列5个句子都是错误的，在书面表达中应当避免：

At the age of five, his father died.

To improve your English, reading is necessary.

Being a fine day, we went out for a play.

While waiting for the bus, my wallet missed.

Giving more time, I can do it better.

上述句子的正确表达应当是：

When he was at the age of five, his father died.

To improve your English, you should read a lot.

It being a fine day, we went out for a play.

While waiting for the bus, I lost my wallet.

Given more time, I can do it better.

个别短语如generally speaking（一般来说）、strictly speaking（严格地说）、judging from...（依据……判断）、to tell you the truth（说实话），作为插入语使用，不受主语和状语的逻辑主语一致的限制。

To tell you the truth, your conclusion sounds strange.

告诉你实话，你的结论听起来很奇怪。