英语总结（八）——目的状语从句

目的状语从句

用法

补充主句中谓语动词所表示的动作发生的目的，
从句中常含 may, might, can, could, will, would 等情态动词。

连接词

in order that, so that, in case, for fear that等

要点

in order that, so that

in order that 比 so that 正式；in order that 引导的从句一般位于句首或者句尾；so that 引导的从句一般位于句尾。
他们引导的从句中常含情态动词

-例句
In order that we might see the sunrise, we started for the peak early.
为了能看见日出，我们很早就向山顶出发了。
She work hard so that everything would be ready in time.
她努力工作是为了让一切及时就绪。

in case, for fear that, lest

表示“以防；以免”。

-例句
Leave your key with your neighbor in case you lock yourself out one day.
留把钥匙给邻居，以防有一天你把自己锁在外面。
We all seemed afraid to say what was in our minds, for fear that it should cause trouble.
我们似乎都不敢说出心里的想法，以防万一引起麻烦。
Take your umbrella wirh you, lest it should rain.
带上你的伞，以防下雨。

区分：lest 和 for fear that 引导的从句中谓语动词用 "should + 动词原形" 表示虚拟

-例句
I am telling you that lest you should make a mistake.
我告诉你那一点，以免你搞错。
The boy hid himself behind the tree for fear that his father should see.
男孩藏在树后面，唯恐他的父亲发现。

so that, in order that 引导的目的状语从句与不定式、介词短语的转换

1）当从句与主句主语一致时，目的状从可用  "so as/in order + 不定式（短语）" 代替， so as/ in order 可以省略。

-例句
He ran fast so that he might arrive there before ten o'clock.
-> He ran fast (so as) to arrive there before ten o'clock.
他跑得很快，以便在十点之前到达那里。
He worked day and night in order that he could succeed.
-> He worked day and night (in order) to succeed.
他日夜工作，为了能获得成功。

2）主从句主语不一致时，目的状从可换为 "in order for sb. + 不定式（短语）" 的复合结构。
I bought my sister a new dictionary so that she could look up new words conveniently.
-> I bought my sister a new dictionary in order for her to look up new words conveniently.

笔者的话：其实这里还有一个 "so as for" 但是笔者并不能很好地总结出一个东西，而且似乎不常用，就姑且放过。

辨析 so that 引导目的状从和结果状从

含义上区别：引导目的状从表示一种意欲或者可能性，结果状从表示一种事实。
形式上区别：目的状从其前不用逗号；结果状从前面通常有逗号。还有一种方法，可看句中是否有 "can/could, may/might, will/would, should" 等情态动词，如果没有，多半是结果状从。
从语义上分析。

He planned his time well do that he could finish his work on time.
他好好地计划了时间，以便能按时完成工作。（目的状从）
He didn't plan his time well, so that he did't finish his work on time.
他没有好好地计划时间，结果没有按时完成工作。（结果状从）