“so…that”句型的化简及活用

表示结果的主从复合句“so…that” 是英语中最常见的句型，也是各类试题常考的热点。“so…that”还可以用“too...to do”或“enough…to do”句型化简成简单句。掌握了其化简规律并能灵和应用，无论对初学者还是对应试者都是有裨益的。本文就此作以下简单归纳。

一.四个基本句型

1.       so …that not→too…to do

2.       so…that→…enough to do

3.       so …that not→too…for sb. to do

4.       so…that→…enough for sb. to do

二.四个基本句型的选用

1.    如果从句是否定句，且主从复合句是同主语就用句型1化简。例如：

He is so weak that he cannot go to London himself. →He is too weak to go to London himself. 他身体很虚弱，不能亲自去伦敦了。

2.    如果从句是肯定句，且主从复合句是同主语就用句型2化简。例如：

They worked so hard that they all passed the test. → They all worked hard enough to pass the test. 他们学习很努力，都通过了考试。

3.    如果从句是否定句，且主从复合句的主语不同就用句型3化简。例如：

It was so early that the train did not arrive. →It was too early for the train to arrive. 天气尚早，火车还没来。

4.    如果从句是肯定句，且主从复合句的主语不同就用句型4化简。例如：

The speaker spoke so well that we all became excited. →The speaker spoke well enough for us all to become excited. 发言人讲得很好，当时我们都很激动。

规律：在把“So…that”句型化简成简单句时，首先要看“that”从句是肯定句，还是否定句：肯定句用“enough…to do”句型化简; 否定句用“too...to do”句型化简。再看主从复合句是主语是否相同：主语相同用“too...to do/enough…to do”句型化简； 主语不相同用“too...for sb. to do/…enough for sb. to do”句型化简。 “for sb.”引导动词不定式“to do”的逻辑主语，即从句的主语。

三. 应注意的几个问题

1.    化简后，如果简单句的主语是动词不等式的逻辑宾语，动词不定式就不能再带宾语了。例如：

    The problem was so difficult that most of the students didn’t work it out. →The problem was too difficult for most of the students to work out. 那个问题太难了，大部分学生都没有做出来。

    The room is so large that the ten of us can live in it. →The room is large enough for the ten of us to live in. 这间房子很大，够我们十个人住。

2.    “too...to do”句型在下列情况下不表示否定，而表示肯定，因此，不能与“So…that”句型的否定句互换。例如：

1). 在该句型中又有否定词，即: 否定之否定表示肯定。例如：

She is too careful not to have noticed it. 他那么细心，不会不注意到这一点的。

Never too old/late to learn. 学习不嫌晚/活到老学到老。

2).在该句型too前有only/but。例如：

I’m but/only too glad to have a talk with you. 能跟你谈谈我很高兴。

3). 该句型中的形容词表示心理活动或品质等，如：glad, happy, kind, anxious, generous, enthusiastic, careful, ect. 例如：

She is too anxious too leave. 他急着要走。

He is too generous to have given away most of his money to charities.他非常慷慨把大部分钱都捐给了慈善事业。

4).动词不定式作真主语。例如：

It’s too much to have him standing all the morning. 叫他站一个上午，这太过分了。

It is too convenient to travel around now! 现在出行真是很方便！

上述句子中要么有否定词、要么有but/only、要么是固定搭配、要么是动词不定式做主语，所以，它们都表示肯定的意思。其中有的可以与“so…that”句型转换，有的则不行，应当引起注意。

3. “such…that” 主从复合句型也可化简成“too…to do/enough…to do”简单句。如果先将其改成“so…that”句型，化简就简单了。例如：

He made such rapid progress in English that he could write in English before long. →His progress in English was so rapid that he could write in English before long. →His progress in English was rapid enough (for him) to write in English before long. 他在英语学习方面进步很快，不久就能用英语写作了。

It is such a cold day that we dare not go out. →It is so cold a day/so cold that we dare not go out. →It is too cold for us to go out.今天天气这么冷，我们不敢出门。

3.     so that引导结果状语从句时也可以有同样的化简。例如：

We started out very early so that we arrived at the destination ahead of time. →We started out early enough to arrive at the destination ahead of time.我们动身得很早，结果提前到达了目的地。

They were very tired so that they didn’t complete the task.. →They were too tired to complete the task.他们太累了没完成任务。

The mountain was extremely high so that the girls didn’t climb it up→The mountain was too high for the girls to climb up.山太高了女孩子们没爬上去。

4.     so…that 还可以引导目的状语从句，这时要用“so as to do/in order to”化简。例如：

He got up early so that he could catch the early bus. →He got up early so as to catch the early bus. 为了能赶上早班车，他起的很早。

此句也可以写成：He got up early in order that he could catch the early bus. →He got up early in order to catch the early bus.

 5. 注意 “so as to do”表示目的，与“so + adj. + as to do”表示程度句型的区别。例如：

She was so kind as to help the old lady off the bus.她心肠真好，主动把那位老奶奶扶下了车。

She stood up first so as to help the old lady off the bus.为了搀扶那位老奶奶下车，她先站了起来。

再试比较下列句子，注意不同句型：

The book was so rewritten that children can enjoy it.（=The book was rewritten so that children can enjoy it.） 这本书是为了使小孩喜欢看，而加以改写的。“so”修饰动词。

It’s so cold (a day) that the pond has frozen. 天气太冷池塘都结冰了。“so”修饰形容词词。

I ran so fast that I’d got a pain in my side. 我跑得太快，结果导致腹侧疼痛。“so”修饰副词。

He was so exhausted that he couldn’t eat dinner. 他疲惫得吃不下饭。“so”修饰分词。

He is so generous as to treat us to dinner every time we meet.他真大方，每次见面都请我们吃饭。

“so’修饰形容词，构成 “so…as to do”句型。