as引导的五种状语从句
as作从属连词用时,可以引导五种状语从句。现归纳如下：
1. as表示“当……的时候”,引导时间状语从句,多强调主句和从句中的动作或状态同时发生,从句可放在主句前,也可放在主句后。例如：
As I waited at the stop, I heard a big noi. 当我在车站等车的时候,我听到一个很大的声响。
She ro up as he entered. 当他进来时,她站了起来。
2. as表示“因为”、“由于”,引导原因状语从句,其语气不如becau强,通常为附加说明的理由,且是已知晓的原因,主句与从句没有逻辑上的因果关系。例如：
As she was not well, I went there alone. 因为她身体不好,所以我独自到那里去了。
As he is a tailor, he knows what to do with this material. 由于他是个裁缝,他知道怎样利用这块布料。
3. as表示“虽然……但是……”,引导让步状语从句,从句通常用倒装语序,把从句的表语、状语或动词原形放在as前面,可以用though替代。例如：
Child as he is, he knows a lot. 虽然他是个孩子,但他知道的东西很多。
Hard as it was raining, they went on working in the field. 虽然天下大雨,但他们继续在田地里干活。结实的反义词
4. as表示“按照”、“依照”、“像”,引导方式状语从句,从句置于主句之后。例如：
You should do as the teacher tells you.你应当依照老师所说的去做。
The abnce of air also explains why the stars do not em to twinkle in space as they do from the earth. 空气的不存在,也说明了为什么在空中星星看来并不闪烁,而不像从地球上看的那样。
5. as表示“像……一样”,引导比较状语从句,对主句和从句的动作或状态加以比较,说明它们之间有相似之处,在从句中常省略与主句相同的部分。例如：
He doesn't work as hard as I (do). 他不像我工作那样努力。
I hope the necklace was as good as the one you lent me.我希望我挂项链同你借给我的一样好。
连词as引导的状语从句
Proud as the nobles are,he is afraid to e me.
在这个句子中，as是一个连词，引导让步状语从句。与常见的让步从句不同的是，这个状语从句的结构有点特殊；表语放在了句首。作为连词，as极其活跃，能引导多种状语从句，本文拟将这一用法作一归纳。
１、引导时间状语从句
As you study a globe,you may notice that most of the large land
areas are connected,or almost so.(高一册，第267页)
As the steam expands,the temperature falls.当水蒸汽膨胀时，温度就下降。
Just as I was backing out,my sleeve caught on the corner of a tray
of diamonds.(高三册，第225页)
２、引导原因状语从句
化粪池施工方案As Li Ping was not well,I went there mylf.(高一册,第96页菠萝蜜的正确剥法)
As water is a good solvent,pure water is never met with in nature.
因为水是一种很好的溶剂，所以在自然界从未遇见过纯水。
as引导的原因状语从句也可以采用倒装结构，如：
Tired as he was,he want to bed at once.他因为很累，所以马上就去睡了。
Michael,fool as he was,completely ruined the dinner.
又与迈克尔的愚蠢，这次宴会给搅乱了。猪展汤
Absorbed as he was in a mathematical problem,he did not notice my
entering the room.由于他全神贯注在解一道数学题，所以没有注意到我走进房间。
But,living as it does in a community of cells,it is not
independent at all.(高二册，第336页)
Living as we do in a remote village,we have few visitors.
由于我们住在一个偏僻的村子里，所以没有什么来客。
３、引导让步状语从句，其结构如下：
1）adj.+as+主语＋系动词be，…
Young as he is,he knows a lot of things.他年龄不大，可知道的事情却不少。
Poor as he was,he was honest.
Hard as steel is,it will bend or break under the action of a strong
c1驾照可以开什么车force.刚虽然很硬，但在强力作用下也会弯曲或断裂。
2）n.+as+主语＋系动词be，…
Child as he is,he knows a lot of things.他虽然是个孩子，可知道的事情却不少。
King as he is,he is unhappy.
Expert as he was,he failed.他虽然是专家,但还是失败了.
注意在本句型中，句首的单数可数名词前不用冠词。试比较下面这个与第一句意义相同的句子：
Although he is a child,he knows a lot of things.
3）adv.+as+主语赏梅+动词，…
Much as I like it,I won’t buy it.尽管我很喜欢它，但我却不买。
Fast as you read,you can’t finish the book in two days.
尽管你读得很快，你也不能在两天之内读完这本书。
4）4）v.(原型)＋as＋主语＋助动词，…
Try as you may,you will never succeed.无论我怎样寻找，也未能发现他的踪影。
４、引导方式状语从句
The abnce of air also explains why the stars do not em to
twinkle in space,as they do from the earth.
(高二册，第198页)太空中没有空气，这也说明了为什么在太空星星看来并不闪烁，不想从地球上看到的那样。
Solids expand and contract as liquids and gas do.
固体像液体和气体一样也会膨胀和收缩。
as在引导方式状语时，前面可以有加强语气的just：
Just as sound is a wave motion,light in the same n,may be
regarded as a wave motion.正如声音是一种波动一样，光也同样可以看作是一种波动。
I knew his wife must be praying for him,just as I was praying for
James.我知道他妻子一定在为他祈祷，正如我为詹姆斯祈祷一样。
Electricity flows through a wire just as water flows through a pipe.
电通过导线,就像水流过管子一样.
什么过成语５、比较状语从句
They produce gas almost as harmful as the gas form factories.
理财易
(高一册，第194页)
You know as much about that as I do.
