SAT语法：连词难点回顾

　　因为连词的种类非常多，有并列连词（连接并列句），有从属连词（引导复合句），而从属连词引导的从句又可分为三类：名词性从句、定语从句和状语从句。尤其应注意的是有些连词可引导不止一种从句，具有多重功能，这往往是学习的难点，也是易混点。

　　难点回顾：

　　1 as可引导多种从句，如时间状语从句、原因状语从句、让步状语从句、方式状语从句、比较状语从句以及定语从句。

　　［误］ Which you can see, he is always ready to help others.

　　［正］ As you can see, he is always ready to help others.

　　［析］as引导非限制性定语从句，当“正像”讲。

　　［误］ Do like I told you.

　　［正］ Do as I told you.

　　［析］like是介词； as是连词，在这里作“按照”讲，引导方式状语从句。

　　［误］ He was reading then he was walking.

　　［正］ He was reading as he was walking.

　　［析］as强调两个动作同时进行，作“一边……一边……”讲。

　　［误］ As he is young, he knows a lot.

　　［正］ Young as he is, he knows a lot.

　　［析］as引导的让步状语从句应用倒装语序，应把表语提前。

　　2.that可引导多种从句，如定语从句、名词性从句、状语从句等。

　　［误］ You don’t like him is none of my business.

　　［正］ That you don’t like him is none of my business.

　　［析］that引导主语从句，本身无实际意义，但不能省略。

　　［误］ The thief handed everything which he had stolen to the police.

　　［正］ The thief handed everything that he had stolen to the police.

　　［析］everything是不定代词，因此后面的定语从句只能由that引导。

　　［误］ I am happy as you passed the exam.

　　［正］ I am happy that you passed the exam.

　　［析］that在形容词后面引导原因状语从句，不能用as。

　　3.where可引导多种从句，如定语从句、状语从句以及名词性从句。

　　［误］ Go to find your watch. It’s there where you left it.

　　［正］ Go to find your watch. It’s where you left it.

　　［析］where引导表语从句，相当于at the place where。

　　［误］ The place where there is water, there is life.

　　［正］ Where there is water, there is life.

　　［析］where引导地点状语从句，可以放在主句的前面，也可以放在主句的后面。

　　［误］ I can’t remember in which place I met him.

　　［正］ I can’t remember where I met him.

　　［析］where引导宾语从句，不能用in which。

　　4.what可引导感叹句、特殊疑问句、名词性从句等。

　　［误］ How an interesting story he told us!

　　［正］ What an interesting story he told us!

　　［析］What an interesting story！=How interesting a story！

　　［误］ I can’t remember the thing what he told me.

　　［正］ I can’t remember what he told me.

　　［析］what引导宾语从句，相当于the thing that。

　　5 no matter+what/who...与whatever/whoever...的区别：前者只能引导让步状语从句，而后者既可引导让步状语从句，也可引导名词性从句。

　　［误］ I will make friends with no matter who shares my interest.

　　［正］ I will make friends with whoever shares my interest.

　　［析］引导名词性从句时只能用whoever。

　　［误］ You must hand in no matter what you’ve found.

　　［正］ You must hand in whatever you’ve found.

　　［析］ 引导名词性从句时只能用whatever。

　　6.whether和if的区别：两者引导名词性从句时都是从属连词，作“是否”讲，本身不作成分，此时句子中往往出现表示“不肯定”意义的一些短语，如not sure/certain, not known/decided,...is still question, depend on等。

　　whether 和if 引导动词后的宾语从句时可互换，但下列情况一般只能用whether:

　　(1) 引导介词后的宾语从句；（2）引导主语从句； （3） 引导表语从句；（4）引导同位语从句；（5）后面出现or not。

　　［误］ If you can pass the exam depends on how hard you work.

　　［正］ Whether you can pass the exam depends on how hard you work.

　　［析］引导主语从句只能用whether。

　　7.while, when, as 引导时间状语从句时的区别：

　　while只能表示“在一段时间或过程中”，即只能表示时间的“一段”，后面一般用进行时或表示状态的结构；when可以表示一段时间，也可表示时间的“一点”；as引导时间状语从句时，表示两个动作同时进行，作“一边……一边……”讲。

　　［误］ I picked up some French words as I was having a holiday in Paris.

　　［正］ I picked up some French words while I was having a holiday in Paris.

　　［析］while强调在……过程中；as说明两个动作同时进行。

　　［误］ We were having classes while someone knocked at the door.

　　［正］ We were having classes when someone knocked at the door.

　　［析］when可表示时间的“一点”，而while不能。

　　8.because, as, since(now that)引导原因状语从句时的区别：

　　because引导原因状语从句时，表示直接的原因，可以回答why的提问；as只能是一种“附加的”理由，不能回答why的提问；since(now that)多表示双方都已很清楚的事实，作“既然”讲。

　　［误］ Because we’ve finished most of the work, let’s have a rest.

　　［正］ Since(Now that) we’ve finished most of the work, let’s have a rest.

　　［析］表示大家都清楚的理由用since(now that)。

　　9.however和as 引导让步状语从句时的区别：

　　however引导让步状语从句时，相当于no matter how,后面跟形容词或副词；as引导让步状语从句时，用倒装语序，即把作状语的副词或作表语的形容词或名词提前，而且如果作表语的是单数名词，前面不加冠词，也可以把谓语动词部分的实义动词提前。

　　［误］ As hard he works, he can’t catch up with his classmates.

　　［正］ However hard he works, he can’t catch up with his classmates.

　　［析］见上述说明。

　　［误］ A model worker he is, he remains modest.

　　［正］ Model worker as he is, he remains modest.

　　［析］as 引导让步状语从句，前面的单数名词前不加冠词。

　　典例调研

　　［例1］ You must put things there you can find them.

　　there→where。此处应由where引导地点状语从句。

　　［例2］ I remember the time as my grandmother was telling stories to me.

　　as→when。when引导名词性从句，表示“……的时候”。

　　［例3］ A child as he was, he looked quite calm in that difficult situation.

　　去掉A，child的首字母大写。as引导让步状语从句时，前面作表语的单数名词前不加冠词。

　　［例4］ Don’t make friends with such people that you think are dishonest.

　　that→as。such...as...搭配在一起用，as引导定语从句。

　　［例5］ He had been admitted by Beijing University made us very happy.

　　句首加That, 把He改为he。that引导名词性从句，本身无实际意义，也不作成分，但不能省略。

　　10. 两个并列连词不能连用，但therefore, then, yet.可以和并列连词连用。

　　You can watch TV, and or you can go to bed.

　　He hurt his leg, and so / and therefore he couldn‘t play in the game.

　　11. although… yet…，但although不与 but连用。

　　(错)Although he was weak, but he tried his best to do the work..

　　(对)Although he was weak, yet he tried his best to do the work.