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从句表示的是主句行为的原因从句表示的是主句行为的原因从句表示的是主句行为的原因通常由because, since, as, for引导 (2)because表示直接直接直接直接原因（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，becausebecause和和和和soso不能同用在不能同用在不能同用在不能同用在一个句子里一个句子里一个句子里一个句子里 例如：--Why aren’t going there? --Because I don’t want to. since 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显然的或已为人知的理由显然的或已为人知的理由显然的或已为人知的理由，语气较because弱 例如：Since the rain has stopped，let’s go for a walk. 既然雨停了，我们出去散散步吧 asas和和和和sincesince语气较弱，语气较弱，一般用来表示明显的原因明显的原因。
由由as和和since引导的原因状语从句多放在句首 例如 ：As he has no car, he can’t get there easily. Since we have no money, we can’t 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 something wrong with my bike. 2. He took off his coat _______ he felt hot. 3.________you can’t answer the question, I’ll ask someone else.becauseforAs/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 computer in order that we might save time. (2)so that可引导目的状语从句，此时可用可引导目的状语从句，此时可用可引导目的状语从句，此时可用可引导目的状语从句，此时可用toto或或或或in order toin order to替换替换替换替换, ,将其改为简单将其改为简单将其改为简单将其改为简单句句句句 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. 二、结果状语从句二、结果状语从句 (1)结果状语从句由so…that, such…that, so that 引导 (2)so…that语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”。
例如： He was so glad that he couldn’t say a word. Mother lives so far away that we hardly ever（几乎不，从来不） see her. 二、结果状语从句二、结果状语从句 (1)结果状语从句由so…that, such…that, so that 引导 (2)so…that语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” 例如： He was so glad that he couldn’t say a word. Mother lives so far away that we hardly ever（几乎不，从来不） see her. （3）so that既可引导目的状语从句目的状语从句目的状语从句目的状语从句，又可引导结果状语从句结果状语从句结果状语从句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情态动词情态动词can, could, may, might等。
B)从意思上看，目的状语从句往往表示的目的很明确，不放在句首目的很明确，不放在句首目的很明确，不放在句首目的很明确，不放在句首 例如： Speak clearly so thatso that they may understand you. (目的状语句) Jack is badly ill so thatso that he has to rest. (结果状语从句) 练习：练习：1.I hurried ________I wouldn't 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？判断以下句子是目的状语从句还是条件状语从句？so thatso thatso that so as to…(so as to…(肯定结构肯定结构肯定结构肯定结构) ) eg. He got up early so as to catch the early train. so as not to…(so as not to…(否定结构否定结构否定结构否定结构) ) eg. He got up early so as not to miss the early train. to… to… eg. He got up early to catch the early train. in order that … in order that … eg. He got up early in order that he could catch the early train. in order to… in order to… eg. He got up early in order to catch the early train.用于目的状语从句，还有：用于目的状语从句，还有： 结果状语从句结果状语从句 (1)结果状语从句由结果状语从句由so…that, such…that, so that引导。
引导 (2)so…that与与 such...that可以互换在由可以互换在由so...that引导的结果状语从句引导的结果状语从句中，中，soso是副词，与形容词连用其结构是是副词，与形容词连用其结构是是副词，与形容词连用其结构是是副词，与形容词连用其结构是: “...so + : “...so + 形容词（副词）形容词（副词）形容词（副词）形容词（副词）+ that + + that + 从句从句从句从句” 例：例： He was so glad that he couldn’t say a word. Mother lives so far away that we hardly ever（几乎不，从来不）（几乎不，从来不） see her. （（2）在由）在由such…that引导的结果状语从句中，引导的结果状语从句中，suchsuch是形容词，它修饰是形容词，它修饰是形容词，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 + : “...such +a / an + 形容词形容词形容词形容词+ +名词名词名词名词+ that + + that + 从句从句从句从句” ”。
例如：例如： 1.It was such a hot daya hot day that nobody wanted to do anything. 2.He had such long arms long arms that he could almost touch the ceiling.（天花板）（天花板） 有时上述两种结构是可以互换的有时上述两种结构是可以互换的 例如：例如： It was such a wonderful filma wonderful film that all of us wanted to see it again. =The film was so wonderful wonderful that all of us wanted to see it again. (3)如果名词前由如果名词前由如果名词前由如果名词前由many, much, little, fewmany, much, little, few等词修饰时，只能用等词修饰时，只能用等词修饰时，只能用等词修饰时，只能用so, so, 不不不不用用用用suchsuch 例如：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 can’t go to the cinema with you. (4)(4)如果主从句的主语相同，并且从句是否定的形式，可以用如果主从句的主语相同，并且从句是否定的形式，可以用如果主从句的主语相同，并且从句是否定的形式，可以用如果主从句的主语相同，并且从句是否定的形式，可以用too...to...too...to...句型转化句型转化句型转化句型转化。
例如：例如： He was so excited that he couldn't go to sleep that night. = He was too excited to go to sleep 5)5)如果主从句的主语相同，但从句是肯定的形式，可以用如果主从句的主语相同，但从句是肯定的形式，可以用如果主从句的主语相同，但从句是肯定的形式，可以用如果主从句的主语相同，但从句是肯定的形式，可以用adj.+ enoughadj.+ enough替替替替换 例如：他够大了，可以去上学例如：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：练习：1.It is ___ hot in the room ___ we have to go out for 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 couldn’t reach it. so thatsuch thatsuch that 强化练习 一、单项选择。
1．We’ll stay at home if it ______ tomorrow. A．rain B．rains C．is raining D．will rain 2．We didn’t go home _____ we finished the work. A．since B．until C．because D．though 3．She ______ when I went to see her. A．is reading B．have read C．was reading D．reads 4．_____ the rain stops, we’ll set off for the station. A．Before B．Unless C．As soon as D．Though 5．She looks forward every spring to ____ the flower garden. A．visit B．paying a visit C．walk in D．walking in 6．Mr. White hoped he ______ China the next year. A．would visit B．will visit C．visited D．has visited 7．I told him that the sun ______ in the east. A．rises B．rose C．has risen D．was rising 。