2017年成人高考专升本英语复习资料-词汇和语法复习:状语从句（2）

4)原因状语从句

　　because， as since， for 皆为“因为”时的区别：

　　a.because 语气最强，用以回答why引导的问句。它可和强调词only， just以及否定词not连用，其所引导的从句常位于主句之后，只有强调时才置于主句之前。Because从句还可以用于强调结构，如It was because I wanted to see my mother that I went to Beijing last month.(It was…that/ It is …that)

　　b.As语气较弱，较口语化，所表的原因比较明显，或是已知的事实，所以不用强调。As从句之前不可用强调句和not， 也不可用于强调结构。As从句多置于主句之前。

　　c.Since 的语气也比较弱，常表示对方已知的事实，往往相当于汉语的“既然”。它和as 一样，其前也不可用强调词和not， 也不可用强调结构。

　　d.For 和上述三个从属连词不同，它是一个等立连词，比较文气。它有时可用来作附加说明，We must get rid of carelessness， for it often leads to errors. 我们一定要克服粗枝大叶的毛病，因为这常导致错误。

5)目的状语从句

　　关联词有so that， in order that， for fear that(以免)， in case(以免)等。

　　Speak clearly so that they may understand you.

　　He spoke slowly in order that everyone should understand.

　　I've got the key in case we want to go inside.

6)结果状语从句

　　关联词有so that， so…that， such…that等。such+名词，so+形容词，副词。

　　It's such a good chance that we can't miss it.

　　He was so angry that he could not speak.

　　Everybody lent a hand so that the work was finished ahead of time.