如果一个从句用作状语，功能相当于副词并修饰动词、形容词或整个句子，那么该从句就是状语从句（Adverbial Clause）。
一、时间状语从句
1.1 由从属连词引导
由从属连词 when（当……的时候）, while（在……期间）, as（正当……时候）, after （在……之后）, before（在……之前）, since（自从……）, till/until（直到……）, whenever（每当……）, once（一旦）等引导。
时间状语从句可以放在句首、句中和句尾。例如：
When I met the Gills, I had been gardening for nearly ten years.
When the owners designed the mall, they wanted it to be more than just a place to shop and eat.
All languages change when cultures communicate with each other.
I met her while I was at school ．
Whenever he is in town, he will stay here．
Once she has made up her mind, nothing can change it．
Take things as they come.
He sat watching her as she got ready.
After we are able to achieve these three goals — of commandments, stability and wisdom, then we can say we have walked onto the correct path for enlightenment.
The value of health is not esteemed until it is lost.
Did she leave a message before she went?
Cath hasn’t phoned since she went to Berlin.
We’ve been waiting here since two o’clock. (介词)
How long is it since we last went to the theatre?
It’s important we waited till the last possible second to get a good shot.
1.2 由起连词作用的词组引导
由起连词作用的词组 as soon as…（一……就……）, scarcely…when…（刚……就……）, no sooner…than…（刚……就……）, hardly…when…（刚……就……），by the time 等引导。例如：
I determined to lodge a complaint as soon as we arrived.
He had no sooner arrived home than he was asked to start on another journey.
I had scarcely thought of her marriage when I wanted to cry.
By the time you came back, I had finished this book.
【特别提示】 在 “hardly（scarcely, rarely）...when…” “no sooner…than…”结构中，主句用过去完成时，从句用一般过去时 。当 hardly, scarcely, rarely 和 no sooner 位于句首时，主句应用倒装语序 。例如：
No sooner had he arrived home than he was asked to start on another journey.
Hardly /Scarcely /Barely had the game begun when it started to rain.
1.3 不由从属连词引导的时间状语从句（名词短语、副词等）
例如：
The moment you leave this tent, you will get a big surprise.
Every time （=Whenever ）I see you, you look younger.
Every time she plays ball games, she wins the game for her side.
Don’t make the same mistakes next time you write.
The second time he spoke, his accent told me that he was from the south.
He sat there silent all the time they were dancing.
Instantly the boy fell, he began to cry.
二、地点状语从句
2.1 由从属连词引导
由从属连词 where（在……地方）, wherever（无论哪里）或 everywhere（到处）等引导。例如：
Cross the stream where it is the shallowest.（谚语）在最浅处过河。
Wherever she goes, there are crowds of people waiting to see her. 她所到之处都有成群的人等着见她。
Everywhere they looked nearly everything was destroyed．他们目光所及之处，只见一切几乎都被毁坏了。
Sit down before fact as a little child. Be prepared to give up every preconceived notion, follow humbly wherever and to whatever abyss nature leads, or you shall learn nothing. （Thomas Henry Huxley）在事实面前要像小孩子一样坐下来，准备好放弃一切先入之见，恭顺地听从自然的指引，无论到哪里，无论什么样的深渊。否则你什么都学不到。（托马斯•亨利•赫胥黎）
We try to help, wherever there is injustice. 凡有不公正的地方，我们都竭力相助予以纠正。
Where the maple leaves fall, the scenery is the most beautiful. 枫叶飘落的地方景色最美。
Where there is life, there is hope．留得青山在，不怕没柴烧。
Where there are heights, there are precipices．高山之巅，必有悬崖。
2.2 连词 where 引导的地点状语从句用于引申意义
连词 where 引导的地点状语从句用于引申意义，例如：
Where there is a will, there is a way.（谚语）有志者事竟成。
Where men are well used, they’ll frequent there．用人得当，人心归向。
There is no poverty where there is virtue, no riches where virtue is not. 有德不穷，无德不富。
Birth is nothing where virtue is not ．如果没有品德，出身再好也枉然。（条件）
Where I was fascinated by the lecture, my brother showed intolerable indifference．尽管那讲座深深吸引了我，我弟弟所表现出来的无动于衷却令人无法容忍。（对比）
Go where you should, keep on studying．无论你到哪里，都应该继续学习。（让步）
【提示】地点状语从句常常可转化为定语从句。
三、原因状语从句
3.1 由从属连词引导
由从属连词或复合连词 because（因为）, as（由于）, since（既然/因为）, for（由于），seeing that（由于）， now that（既然），considering that , on the ground(s) that 等引导。例如：
Because natural light changes so quickly, the impressionists had to paint quickly. 因为自然光变幻很快，印象派画家们得快速作画。
Examinations are nothing but anxiety makers, because they tend to be considered as marks of success and failure ．考试只不过是焦虑的制造者，因为考试往往被看作是成功与失败的标志。
I smoked with concentration and pleasure as I was sure that this would be my last cigarette. 我聚精会神而又愉快地吸着这支烟，因为我确信这是我最后一支烟了。
As riddle guessing is interesting and full of wisdom, it has become popular among all walks of life．由于猜谜语很有趣且充满智慧，它在各行各业中都很流行。
As the medicine took effect, the symptoms lessened. 因药力奏效，症状减轻了。
Since I was better educated, I got a job working in an office. 因为我受过比较好的教育，我得到了一份坐办公室的工作。
Now that a tunnel has been built through the mountains, the Pass is less dangerous．既然在山里已通了隧道，这山口就不再那么危险了。
Now that they are just beginners, they are doing quite a good job．既然他们是新手，所以干得还不错。
Now that you mentioned it, I do remember the funny clown．经你一提，我真的就想起那个滑稽的小丑了。
3.2 某些形容词后面跟由 that 引导的从句也表示原因（that有时可以省略）
例如：
We were greatly disappointed that many stars were absent from the Film Festival. 许多明星缺席电影节让我们大为失望。
They are proud that Shanghai is getting more and more beautiful. 他们自豪的是，上海变得越来越美丽了。
We are not pleased that we can’t use underground water ．我们对不能使用地下水感到很不满。
He is amazed that the small boy is strong enough to lift the stone. 他感到惊讶这个小男孩竟然有足够的力量举起石头。
They are puzzled that the hero was criticized rather than rewarded ．他们困惑的是英雄受到了批评，而没有得到报答。
3.3 需要注意的用法要点
3.3.1 because, as, since 的用法区别
三者都表示原因，但语气程度不同：because 表示“原因”的语气最强，尤其强调与主句的因果关系，说明别人不知道但想知道的原因，也用于回答why 的提问; as 表示“原因”时语气不如 because 强，它所说明的原因往往显而易见；since的语气与as相似，它表示的原因多少是对方已经知晓的。例如：
I did it because I was very angry ．我干的，因为我当时愤怒极了。
As you did it, you are to explain to him．因为是你干的，你去向他解释。
Since she doesn’t want to come, we’ll have to go．既然她不愿意来，我们就得去。
3.3.2 for 表示原因
【解释一】
for 不是从属连词而是等立连词，它引导的不是从句而是分句，它所引导的分句只能放在句子后部，而且常用逗号或分号把它和前面的分句隔开，它表示的原因往往是作为对上文的进一步解释。
【解释二】
for 引导的分句只是对前面分句加以解释，说明推断的理由，并且只能后置。
例如：
No one can plead ignorance of a subject any longer, for there are countless do-i-t yourself publications.
I didn’t go to see him for a heavy rain was falling .
There must be no one in the house for the light is off .
It is going to rain, for the dark clouds are gathering .
Something bad must have happened in the street, for a police car was seen.
3.3.3 英语书面语中还可用 in that 引导原因状语从句
例如：
Criticism and self-criticism is necessary in that it helps us to correct our mistakes. 批评与自我批评是必要的，因为这能帮助我们改正错误。
The situation is rather complex in that all the staff have different family backgrounds. 由于所有的职员家庭背景不同，所以情况很复杂。
A liquid differs from a solid in that it has no definite shape． 液体不同于固体就在于它没有一定的形状。
Practice is valuable in that it can solve practical problems． 实践之所以有价值，就在于它能解决实际问题。
The novel is unsatisfactory in that it lacks a complete plot． 这本小说不太令人满意，理由是缺少完整的情节。
3.3.4 that 引导的从句
表示心理感情的形容词后可跟 that 引导的从句表示原因。例如：
I am sure that he will go to visit you. 我确信他会去看望你的。
She was happy that she could play to her heart’s content. 她高兴的是可以尽情地玩耍。
四、结果状语从句
由从属连词 so that（结果）或 so…that/such…that（如此……以至于）引导。
用法如下：
1 | so + 形容词/副词 + that 从句； |
例句：
The scientist’s report was so instructive that we were all very excited.
He was so angry that he couldn’t speak. = He was too angry to speak.
I have been so occupied getting used to everything that I haven’t had time for social activities.
The Ocean Park is such a huge place that visitors often use shuttles to get around.
A compromise is the art of dividing a cake in such a way that everyone believes that he has got the biggest piece .（Ludwig Erhard）折中是一种这么分蛋糕的艺术：每个人都以为自己得到了最大的一块。（路德维希•艾哈德）
He has put forward unquestioned claims so consistently that he not only believes them himself, but has convinced industrial and business management that they are true． 他对实验结果所下的结论是如此毋庸置疑、如此的一致，以致于不仅让他本人，而且也让工商管理部门相信其预料的准确性。
The transportation of that country was very poor so that few big corporations would like to invest there.
【特别提示】 that引导的从句
What have I done that you should be so angry with me ？我做了什么使你这么生气 ？
He is vain that they all dislike him．他很虚荣，他们都不喜欢他 。
In Kunming the climate is mild that the grass keeps green all the year round ．昆明的气候非常温和，所以草儿四季常青 。
五、目的状语从句
5.1 由从属连词（so）that（以便，为了）, in order that（为了）等引导
由从属连词 （so）that（以便）, in order that（为了）等引导，表示将要实现的一件事情。从句带有情态意味，所以从句谓语一般带有情态动词。常用的情态动词是 may或might，但so that引导的从句中也可以用 can/could 或 will/would。例如：
I opened the window so that the fresh air might come in．我把窗户打开以使新鲜空气进来。
They may play to passers-by in the street or subway in order that they can earn some extra money．他们可能在街上或地铁里为过路者演奏，这样他们可以多挣一些钱。
For another, the university should make a careful arrangement of selective courses so that they can facilitate instead of hindering normal study ．另一方面，大学应该仔细安排选修课，以便能够促进而不是妨碍正常学习。
A man desires praise that he may be reassured ．人想要得到称赞以图放心，以图消除自我疑虑。
Humor can help you cope with the unbearable so that you can stay on the bright side of things until the bright side actually comes along. （Allen Klein）幽默可以帮助你应付不堪忍受的遭遇，从而处于境况的光明一面，直至光明一面真正到来。（艾伦•克莱恩）
【特别提示】 in order that 常用于正式文体，可置于句首，也可置于句尾 ；而 so that 常常位于句尾， so that 短语有时可省略 that。例如：
The lawn was fenced outside so (that) nobody could get in． 草坪外面围着栅栏，以便人们不能进入 。
5.2 由从属连词lest（唯恐、以防）, for fear that（以防）, in case（以防）等引导
由从属连词 lest（唯恐、以防）, for fear that（以防）,in case（以防）等引导，表示旨在避免的状况。例如：
She lowered her voice lest her parents should hear the secret she was telling me．她压低了嗓音，以防她父母听到她正告诉我的秘密。
I dare not go there for fear that they will see me．我不敢去那儿，怕被他们看见。
Please write the address on a piece of paper in case you forget． 请把地址写在纸上，以免忘记。
The boy hid himself in a large tree for fear that /in case the enemy find him． 那孩子躲在一棵大树上，以防敌人发现他。
5.3 连词 so that 引导结果状语从句与引导目的状语从句时的区别
引导结果状语从句时，连词so that 之前常有逗号与主句隔开；引导目的状语从句时，连词 so that之前不用逗号。从语义逻辑来看，so that 引导的结果状语从句中的动作是主句动作已造成的结果，而 so that引导的目的状语从句中的动作是主句动作将要实现的目的。例如：
The door was open, so that anyone passing could look in ．门开着，所以任何人路过都能看到里面的情况。（表结果）
I packed him a little food so that he wouldn’t get hungry ．我让他带了些食物，以便他不会饿着。（表目的）
They started out early, so that they arrived there in time． 他们早早出发，结果及时赶到了那里。
5.4 目的状语从句与简单句的转换
They shouted loudly so that they could be heard .
→ They shouted loudly so as to /in order to be heard.
The teacher explained his lecture clearly so that the students could understand .
→ The teacher explained his lecture clearly for the students to understand.
He went to the airport in order that he could see his friends off.
→ He went to the airport in order to see his friends off.
【特别提示】 如果主从句的主语不一致，如改为不定式，则不定式前面须由 for 引出逻辑主语 。例如：
My father gave me ten dollars so that I could eat lunch outside.
→ My father gave me ten dollars (in order) for me to eat lunch outside.
I stepped aside so that the boys might pass by.
→ I stepped aside for the boys to pass by.
六、方式和比较状语从句
方式状语从句（Adverbial Clause of Manner）可由下列引导词引导：
as （如同）, as if （好像）, as though, the way, how 等。
6.1 由从属连词 as, as if/as though 等引导
例句：
she closed her eyes as though/as if she were tired.
It looks as if the weather may pick up very soon ．看来天气很快就会好起来。
Do it the way (that) you were told.
You can arrange your time here however you like ．你在这儿的时间随你自己安排。
When at Rome, do as the Romans do .（谚语）入乡随俗。
As water is to fish, so air is to man．人类离不开空气，犹如鱼儿离不开水。
Nothing is so certain as the unexpected ．天有不测风云，人有旦夕祸福。
Difficulties strengthen the mind, as labour does the body ．艰难磨炼意志，劳动强身健体。
In important matters, we expose our best sides; in trivial matters we disclose ourselves as we really are. （Sebastien-Roch Nicolos Chamfort）我们在重要的事件中显示自己最好的方面，在无关紧要的小事中露出自己的本来面目。（尚福尔）
【特别提示】
① 若 as if 后面所指的事情是不可能发生的，从句中的谓语动词要用虚拟语气。例如：
He looks as if /as though he had been hit by lightening ．他那样子就像被雷击了似的 。（与事实相反，谓语用虚拟语气 ）
② 另外， as if/as though 也可以引导一个分词短语或不定式短语 。例如：
He stared at me as if seeing me for the first time ．他目不转睛地看着我，就像第一次看见我似的 。
③ 在美国英语中， like 可以代替 as。例如：
You should do like I do．你应该像我做的那样去做 。
6.2 由连词 than（比）引导的比较状语从句
由连词 than（比）引导。例如：
My life is a lot easier at high school than it was at primary school．我在中学的生活要比我在小学时便利多了。
It is a thousand times better to have common sense without education than to have education without common sense. （Robert Green Ingersoll）具备常识而缺乏教育胜过受到教育而缺乏常识一千倍。（罗柏特•格林•英格索尔）
To many, total abstinence is easier than perfect moderation. （Saint Augustine）对于许多人来说，完全戒绝比恰当节制容易。（圣•奥古斯丁）
A friendship founded on business is better than a business founded on friendship. （John D.Rockefeller）建立在业务上的友谊胜过在友谊上建立的业务。（约翰•D•洛克菲勒）
Men prize the thing ungained more than it is .（William Shakespeare）人们把没到手的东西看得比到手的东西更珍贵。（威廉•莎士比亚）
6.3 由 as…as（和……一样）或not so/as…as（和……不一样）引导的比较状语从句
由 as…as（和……一样）或not so/as…as（和……不一样）引导。例如：
They are as wealthy as a king ．他们像国王一样富有。
The work is not so difficult as you imagine ．这工作不像你想的那么困难。
State capitalism is not as effective as private capitalism ．国家资本主义比不上私人资本主义有效率。
He behaved as generously as a millionaire ．他像百万富翁一样慷慨大方。
He will be earning only half as much as he used to ．他将来挣的钱只有他现在的一半。
6.4 由 as…so…（与……同时，就像……一样）引导的比较状语从句
由as...so…（与……同时，就像……一样）引导。例如：
As you make the bed, so shall you lie on it．你自作自受。
As fire tries gold, so adversity tries virtue．如烈火炼真金一样，逆境考验人的品德。
As bodies need food, so machines need oil.
【特别提示】 注意以下 as 用于表示比较的结构：
Water is to fishes as air is to men.
=Water is to fishes what air is to men.
= As air is to men, so water is to fishes.
= Just as /As air is to men, so is water to fishes.
Tea is to the Chinese as wine is to the French, as beer is to the Germans．对于中国人来说，茶就像法国人的葡萄酒和德国人的啤酒一样必不可少。
6.5 the more…, the more..．结构（比较）
the more…, the more..．结构。例如：
The more careful you are, the fewer mistakes you will make．你越小心出的错就越少。
The more one tries to hide, the more one is exposed．欲盖弥彰。
The sooner you treat your son as a man, the sooner he will be one.（John Locke）越早把孩子当成大人，他越早成为大人。（约翰•洛克）
The richer one is, the greedier he gets．人越有钱越贪婪。
The longer he waited, the more impatient he was getting．他等得时间越久，就越不耐烦。
七、让步状语从句
7.1 由从属连词 though, although, while, whereas, as, even if/even though 等引导
由从属连词 though（虽然）, although（虽然）, while（尽管/而……）, whereas（而……）, as（尽管）, even if/even though（即使）等引导。
例如：
Though/Although he has a lot of money, yet he is unhappy.
Though he was reluctant to do so at first, we eventually persuaded him to take us．
While I don’t really like art, I find his work impressive.
【特别提示】 当 though 或 although 引导让步状语从句时，主句中不能用 but，但是 though或 although 可以和 yet、stil 等用在同一个句子中 。although不可充当副词， though却可以 。even if/even though 语气更强烈，意为 “即使，退一步说 ”。
while 引导让步状语从句时，一般只用于句首 。例如：
Though young and attractive in appearance, she is dignified and reserved．虽然她显得年轻且楚楚动人，却很沉稳持重。
People are unable to find enough time to read extensively even if they intend to ．即使人们想找到充足的时间广泛阅读，也无法做到 。
Big as China is, most of the Chinese people have crowded in the eastern part of the country, making farming their mainstay．尽管中国幅员辽阔，大多数中国人却聚集在东部地区，把农业当作自己的主业 。
7.2 由“no matter（不论）+疑问词”引导
由 “no matter（不论）+疑问词”引导， no matter how/what/where/when… 。
Don’t open the door, no matter who comes.
Don’t trus him, no matter what(=whatever) he says.
No matter how (=However) hard I work, there is always more to do.
I will eat whatever you give me. (whatever 引导宾语从句)
No matter what the conditions were, he believed that a car should be driven as fast as it could possibly go．不管路面情况如何，他认为车必须以最高的速度行驶。
No matter where you live, you would find it difficult not to laugh at, say, Charlie Chaplin’s early films．不管你生活在哪里，你看了诸如查理•卓别林的那些早期电影很难不发笑。
Life is a journey that must be traveled no matter how bad the roads and accommodations. （Oliver Goldsmith）人生是不管道路和食宿多差都得走完的旅程。（奥利弗•戈德史密斯）
No matter where the rumor comes, it can’t be believed by the wise．谣言止于智者。
7.3 由 as（虽然）引导
由 as（虽然）引导，从句须部分倒装，被倒装的部分可以是表语、状语或动词原形。
例如：
Amazing as it may seem, Wednesday night was a quiet night．尽管看起来令人惊疑，星期三的夜晚很宁静。
Child as he was, he knew what was the right thing to do．虽然他是一个孩子，但他知道该做什么。（须省略child前的冠词）
Object as you may, I’ll go．纵使你反对，我也要去。
Eloquent as you are, you won’t persuade her．尽管你口才好，却说服不了她。
Try as they might, they couldn’t start the car．他们想尽了办法，可就是无法将车启动。
Much as I admire him as a genius, I don’t like him as a man．他作为天才我很钦佩，但我不喜欢他的为人。
7.4 由 whether…or… 引导
由 whether…or…（不管是……还是……）引导。例句：
The moon is a moon still, whether it shines or not .（谚语）不管亮不亮，月亮终归是月亮。
Whether you believe it or not, it’s true．无论你是否相信，这都是真的。
Man almost can’t do without music, whether you admit it or not ．无论你是否承认，人类几乎离不开音乐。
Whether he comes here or we go there, the task has to be finished on time．不论他来这里或是我们去那里，任务必须准时完成。
Whether we work or sleep, are earnest or idle, rejoice or moan in agony , the river of time flows on with the same resistless flood．无论我们工作或是睡觉、热心或是怠惰、欣喜或是愁苦，时间的长河总是以不可抗拒的水势向前流去。
7.5 其他引导词
其他引导词有：however（尽管），whatever（不管），granted that（即使），for all that（尽管如此），in spite of the fact that, regardless of the fact that 等。
八、条件状语从句
8.1 由从属连词 if（如果）, unless（除非）, so long as/as long as（只要）等引导。
由从属连词 if（如果）, unless（除非）, so long as/as long as（只要）等引导。例如：
It’s OK to leave an electrical appliance on so long as you are using it ．在使用电气设备时你可以把它开着。
One will not reach the rich storehouse of knowledge unless he studies carefully ．除非认真学习，否则一个人就无法接近丰富的知识宝库。
As long as you’ve paid in advance we won’t charge you for delivery．只要你预先付款，我们就不收你的送费。
We will stay at home if it rains.
If you need money, I can lend you some.
What would happen to your family if you were to die in an accident?
I want to get back by five o’clock if possible.
8.2 由 suppose/supposing（假设）, provided/providing（假若）, on condition that（条件是）等引导
由 suppose/supposing（假设）, provided/providing（假若）, on condition that（条件是）等引导。例如：
You may borrow the book on condition that you don’t lend it to anyone else． 你可以借阅这本书，条件是你不能转借给他人。
Provided people around them speak a language consistently, children display an amazing ability to become fluent speakers of the language．只要周围的人们一直说某种语言，孩子们就会显示出流利地讲这种语言的惊人能力。
Providing there is too much rain, there will be a flood．假如雨量太大，就会出现洪涝。
Supposing you would know the value of money, go and try to borrow some．要想知道钱的价值，就想办法去借钱试试。
8.3 需要注意的用法要点
8.3.1 真实条件句 vs．非真实条件句
条件状语从句所表示的条件有两种：真实条件（有可能实现）和非真实条件（不可能实现）。
若是非真实条件，从句中的谓语动词则需要用虚拟语气。例如：
If I were you, I would leave now.
We should have arrived if we had catched the early train.
I could have warned you if I have know where you were.
8.3.2 连词 unless 有时可与 if…not 通用。
例如：
I will stay at home unless I am invited .（=I will stay at home if I am not invited .）除非受到邀请，不然我将待在家里。（=如果不被邀请，那我就待在家里。）
8.3.3 有时once引导的状语从句强调的是条件。
例如：
Once you know the rules of sprint, you will be able to run really fast．你一旦掌握了短跑的规律，就能跑得很快。
Once you are followed by him, you can’t hope to escape．一旦你被他盯上，就休想逃掉。
8.4 其他条件引导词
其他的引导词还有： only if (只要)，if only （但愿······ 就好了），in the event that, in case that 等。例如：
Investors are completely rational. They take risks only if they get paid for doing so.
If only I could have helped put matters right.
In the event that any Republicans would vote against repeal, they could use an extra one or two votes for safe keeping.
We should not climb the fence of the school in case that we might hurt ourselves.
九、状语从句中省略主语的情况
省略形式的状语从句的构成：
╱ 动词：不定式/现在分词/过去分词
从属连词 +
╲ 非动词：名词/形容词/副词/介词短语
当状语从句的主语与主句的主语一致时，通常可省略主语。谓语动词是行为动词的省略见动词的非谓语形式；谓语是系动词加名词、形容词、副词或介词短语等的，直接由从属连词接名词、形容词、副词或介词短语。此类从属连词有 when, while, whenever, once, till, as if, unless, though, although, where, wherever等。例如：
9.1 从属连词+非谓语动词
But when first published, The Great Gatsby , on the other hand, sold only 25,000 copies．但是，第一次出版时，《了不起的盖茨比》只卖了25 000本。
Unless changed, this law will make life difficult for farmers．除非改变这项法律，否则农民的日子不好过。
If utilized effectively, this power station may produce much power．如加以有效利用，这个电站可以生产许多电。
Once cleared, the site will be very valuable．这块地皮一经清理，便会大大地增值。
While debating, he never forces others to accept his opinion．辩论时他从不强迫别人接受他的观点。
9.2 从属连词+名词
He could recite many poems when yet a child ．他还是孩子时就能背诵很多诗歌。
I must marry her whatever the cost． 无论代价如何，我也要娶她为妻。
Although the youngest of the family, she is the cleverest.
Though a small boy, he has finished middle school.
9.3 从属连词+形容词
If not considerate enough, a man may lose the favor of his girlfriend．如果一个男人不够体贴，就可能失去女朋友的好感。
Whenever possible, the jobs are given to local people．只要有可能，总是为本地人提供就业机会。
While ready to go to him, I wonder where he is．虽然我乐于去他那里，却不知道他在哪里。
He didn’t find the error till too late ．等他发现错误时已经太晚了。
If necessary, you can turn to me for help.
When young, I never think of death.
9.4 从属连词+副词
Here, as elsewhere, money counts．这里也和别处一样，金钱主宰一切。
His memory is not as then （=as it was then）．他的记忆力现在不如以前了。
Father is happier than ever （=than he has ever been）．父亲比过去任何时候都幸福。
Prices were beginning to rise, even if not quickly enough.
Once home, he took off his raincoat.
9.5 从属连词+介词短语
When in doubt about the meaning of life, read some good books．当你对人生的意义表示怀疑时，就读一些好书。
I got to know this pretty girl while on tour． 我是在旅行时认识这位漂亮女孩的。
He is always finding fault with others except when in thoughts． 除非陷入沉思，他总是在挑剔别人。
He fainted while at work.
He looked straight at it as if in doubt.
【特别提示】
① 请看下列省略表达法：
when alone even as a boy if possible
where necessary if in doubt though very old
though not good as though out of curiosity
② 此类复合句 （谓语动词是系动词或行为动词 ）的模式，例子如下：
Although weak in appearance, he is very brave．虽然他表面软弱，可是却很勇敢 。
Health is never valued till lost ．失去健康才知道其价值 。
I knew a lot about the place while on a tour ．我在旅途中才熟悉了这个地方 。
She made a gesture as if to ask for something．她做了个手势，好像要什么似的 。
Every thing, whether large or small, should be considered．每件事无论大小都应认真考虑 。
参考书目：
《综合英语语法》. 王辉，冯秀红编著．—南京：东南大学出版社
《专四语法与词汇》.《专四语法与词汇》编写组编. 世界图书出版公司
本文仅供个人学习、参考。禁止任何商业用途。
