1、原因状语从句原因状语从句 (1)原因状语从句：从句表示的是主句行为的原因。通常由because,since,as,for 引导。(2)because 表示直接原因（听话人所不知的），语气最强。回答由why提出的问题，只能用 because。此外，because 和so不能同用在一个句子里。例如：-Why arent going there?-Because I dont want to.since 相当于now that，“因为，既然，鉴于”表示显然的或已为人知的理由，语气较because弱 例如：Since the rain has stopped，lets go for a walk.既然
2、雨停了，我们出去散散步吧。as和since 语气较弱，一般用来表示明显的原因。由as和since引导的原因状语从句多放在 句首。例如：As he has no car,he cant get there easily.Since we have no money,we cant buy it.(4)for表示所说的理由是一种补充说明,for引导的从句一般不放在句子的开头。如:I decided to stop and have lunch,for I was feeling quite hungry.Eg:1.I was late for class yesterday _ there was
3、 something wrong with my bike.2.He took off his coat _ he felt hot.3._you cant answer the question,Ill ask someone else.because for As/since 目的状语从句目的状语从句 目的状语从句:从句表示的是主句行为的目的从句表示的是主句行为的目的 (1)通常由 so that,in order that（为了，以便）引导。例:We started early so that we could catch the first train.We used the comp
4、uter in order that we might save time.(2)so that可引导目的状语从句，此时可用 to或in order to 替换,将其改为简单句。例如：He got up early so that he could get to school on time.=He got up early（in order）to get to school on time.（3）so that既可引导目的状语从句目的状语从句，又可引导结果状语从句。区别这两种从句的办法有两个：A)目的状语从句里往往带有 情态动词情态动词can,could,may,might 等。B)从意思上
5、看，目的状语从句往往表示的 目的很明确，不放在句首。例如：Speak clearly so that they may understand you.(目的状语句)Jack is badly ill so that he has to rest.(结果状语从句)练习：练习：1.I hurried _I wouldnt be late for class.2.We should go by bus _ we can get there earlier.3.May I sit nearer_ I can see more clearly?判断以下句子是目的状语从句还是条件状语从句？判断以下句子是目
6、的状语从句还是条件状语从句？so that so that so that so as to(肯定结构)eg.He got up early so as to catch the early train.so as not to(否定结构)eg.He got up early so as not to miss the early train.to eg.He got up early to catch the early train.in order that eg.He got up early in order that he could catch the early train.in
7、 order to eg.He got up early in order to catch the early train.用于目的状语从句，还有：结果状语从句结果状语从句(1)结果状语从句由 sothat,suchthat,so that 引导。(2)sothat 与 such.that 可以互换。在由 so.that 引导的结果状语从句中，so是副词，与形容词连用。其结构是:“.so +形容词（副词）+that+从句”。例：He was so glad that he couldnt say a word.Mother lives so far away that we hardly e
8、ver（几乎不，从来不）see her.（2）在由suchthat 引导的结果状语从句中，such 是形容词，它修饰是形容词，它修饰的可以是单数或复数可数名词，也可以是不可数名词；其结构是:“.such+a/an+形容词+名词+that+从句”。例如：1.It was such a hot day that nobody wanted to do anything.2.He had such long arms that he could almost touch the ceiling.（天花板）有时上述两种结构是可以互换的。例如：It was such a wonderful film t
9、hat all of us wanted to see it again.=The film was so wonderful that all of us wanted to see it again.(3)如果名词前由many,much,little,few等词修饰时，只能用so,不用such。例如：A.Soon there were so many deer that they ate up all the wild roses.B.He has so little time that he cant go to the cinema with you.(4)如果主从句的主语相同，并且从
10、句是否定的形式，可以用too.to.句型转化。例如：He was so excited that he couldnt go to sleep that night.=He was too excited to go to sleep 5)如果主从句的主语相同，但从句是肯定的形式，可以用 adj.+enough替换。例如：他够大了，可以去上学。He is so old that he could go to school.=He is old enough to go to school.练习：1.It is _ hot in the room _ we have to go out for
11、a walk.2.It was_a wonderful movie_all of us wanted to see it again.3.There was_little water in the bottle _ the bird couldnt reach it.so that such that such that 强化练习 一、单项选择。1Well stay at home if it _ tomorrow.Arain Brains Cis raining Dwill rain 2We didnt go home _ we finished the work.Asince Buntil
12、 Cbecause Dthough 3She _ when I went to see her.Ais reading Bhave read Cwas reading Dreads 4_ the rain stops,well set off for the station.ABefore BUnless CAs soon as DThough 5She looks forward every spring to _ the flower garden.Avisit Bpaying a visit Cwalk in Dwalking in 6Mr.White hoped he _ China the next year.Awould visit Bwill visit Cvisited Dhas visited 7I told him that the sun _ in the east.Arises Brose Chas risen Dwas rising
