何时加ing何时变原型

结构中；主语＋动词＋it＋形容词＋不定式。

【例如】

We found it impossible to get everything ready in time.

I think it important to learn English well in college.

使用这种句型的常见动词有：believe, consider, declare, feel,

find, guess, imagine, prove, realize, suppose, think,等。

1.不定式的时态的选用

1）不定式的一般式表示不定式的动作与谓语动词的动作同时或在谓语动词动作之后发生。

I saw him enter the room．我看见他进入了那房间。

I was invited to the party to be held in the roof garden．我被邀请参加在屋顶花园举行的晚会。

2）不定式的完成式表示不定式的动作在谓语动词的动作之前发生。

I'm sorry to have kept you waiting so long．很抱歉让你等了那么长时间。

I heard you have finished your job．听说你已经完成了你的工作。

3）不定式的进行式表示不定式的动作在谓语动词的动作发生时正在进行。

They seemed to be eating something．他们好像正在吃东西。

I am very glad to be working with you．很高兴和你一起工作。

2. 不定式的语态

不定式的语态与不定式表示的动作的被动与否以及它与逻辑主语的关系有关。

1）通常而言，不定式的动作是主动的，则不定式用主动语态，反之则用被动语态。

2）在实际运用中还要考虑不定式的逻辑主语。

不定式的逻辑主语是全句的主语：He hurried there to find the train had gone．他赶到那里结果发现火车已经开走了。

主语补足语： Nobody will be allowed to leave unti l7：00a．m．直到七点才允许离开。

宾语：She dislikes to be told to do what she dislikes．她不愿听人使唤。宾语补足语是全句的宾语：Father desires me to be a doctor．父亲希望我当医生。

定语是其中心词：These are the letters for him to be typed today．这些是他今天要打印出来的信笺。

句中某一名词或代词：He bought a book to read．他买了一本书（自己）读。He bought me a book to read．他给我买了一本书读。

主语和表语由for引出：It is impossible for him to do the job alone．他不可能独自干这活。

由of引出：It is very kind of you to see us．谢谢你来看我们。 不

在句中，可根据句义推测出来：My job is to teach students English．我的工作是教学生英语。 分词

英语上的分词分为现在分词和过去分词。

现在分词和过去分词主要差别在于：现在分词表示"主动和进行"，过去分词表示"被动和完成"(不及物动词的过去分词不表示被动，只表示完成)。分词可以有自己的状语、宾语或逻辑主语等。

1、 分词作状语分词在句子中作状语，可以表示时间、条件、原因、结果、让步、伴随等。

分词在句子中作状语，使用何种分词，要取决于分词与句子主语的关系：主谓关系用现在分词，动宾或被动关系用过去分词。

（1）现在分词The students went out of the classroom, laughing and talking.

（2）过去分词Accompanied by his friend, he went to the railway station. Given better attention, the plants could grow better.

2、"while ( when, once, until, if , though等连词)＋分词"结构现在分词或过去分词作状语时，有时可以在分词前加while，when, once, although, until, if等连词。

When leaving the airport, she waved again and again to us. While waiting for the train, I had a long talk with my sister about her work??

Once recovered, he threw himself into his work and made every effort to do it well.

Although working very hard, he failed to pass the final exam. If translated word by word, the passage will be difficult to understand.

3、分词作定语分词作定语时，单个的分词通常放在被修饰的名词之前，分词短语一般置于所修饰的中心词后面。现在分词修饰的是发出该动作的名词(即与名词有主谓关系)，过去分词修饰承受该动作的名词(即与名词是动宾关系)。

We will go on with our experiment as soon as we get the added fund.

This is really an exhausting day to all of us!

We can see the part of the moon lighted by sunlight.

After a night spent in excitement and sleeplessness, I forced myself to take a long walk along the beach the next day.

More and more developing countries established strategic partnership with developed countries

4、分词作宾语补足语现在分词在see, watch, hear, observe, notice, feel, find, glimpse, glance等感官动词和look at, listen to等短语动词以及have, keep, get, catch, leave, set, start, send等使役动词后面与名词或代词构成复合宾语，作宾语补语的成分。

5、分词作表语分词作表语通常看作形容词来用。现在分词表示主语的性质，而且主语多为物；过去分词表示主语的感受或状态，主语多为人。 是你要详细的。。。