高中英語語法it的用法
下面是小編搜集整理分享的高中英語語法it的用法，一起來看看吧。
It用法及其句型和固定搭配，是高中英語語法的重點、難點，又是高考英語的熱點，因此應給予充分的重視，現將it用法歸納如下：
一、作人稱代詞
1、it代替前面(或后面)的單數名詞或分句等所表示的事物。
e.g. You cannot eat your cake but have it.(it代替前面的cake)Although we cannot see it, there is air all around us. (it代替后面的air)They say he has left town, but I don’t believe it. (it代替前面They…town分句中的情況)
2、代替有生命但不能或不必分陰陽性的東西(包括嬰兒)。
e.g. Yesterday we saw a big tree. It was fully twenty metres high. (it代替前面的tree)The baby cried because it was hungry. (it代替前面的baby)
3、在某些習慣說法中，可以代替人。
e.g. -- Someone is knocking at the door, Peter. -- Who is it? -- It’s me.
-- Who are singing? -- It is the children.
-- The light is still on in the lab. It must be the third-year students doing the experiment.
4、it與one的區別：這兩個詞都可以代表前面說過的名詞，但it用于同名同物的場合;one則用于同名異物的場合。
e.g. -- Do you still have the bicycle? -- No, I have sold it.
-- Is this knife yours? -- No. It is Xiao Zhang’s. Mine is the one on the desk.
5、it與that的區別：兩詞都可代替某一特定名詞，但that指同一類，并非同一個。
e.g. The climate of South China is mild(溫和的); I like it very much.(it指the climate of South China)The climate of South China is much better than that of Japan.(that指the climate)
二、作無人稱代詞it作無人稱代詞時，除了句中找不到它所代表的詞語外，另一個特點是它后面的內容都是表示天氣、時間、距離、度量衡及情況等。
It is fine (rainy, windy, etc.).
It is noon.
It is a half hour’s walk to the factory.
It is eighteen square metres in area.
What does it matter?
三、作強調詞，構成強調結構用以幫助改變句子結構，使句子的某一成分受到強調。“It is (was) + 所強調的成分+ that (who) + 其它成分。”在這個句型中，it本身沒有詞義。在使用強調句型時需注意以下幾點：
1. 請注意強調句型的特殊疑問句例When was it that he changed his mind to take part in the activity?
2. 在強調原因狀語從句時，只能強調由because所引導的從句例It was because he was ill that he didn't come to school yesterday.
3. 在強調not … until結構時必須把not與until一起放到被強調的位置上例It was not until she took off her dark glasses that I realized she was my brother.
4. 注意強調句型與定語從句的區別例It was at 7 o'clock that he came here yesterday.( 強調句型)It was 7 o'clock when he came here yesterday.(定語從句)四、It用作形式主語It替代作主語的從句、動詞不定式、動名詞，而把真正作主語的從句、動詞不定式、動名詞置于句尾。
【高中英語語法it的用法】相關文章：
英語語法build用法08-31
英語語法從屬連詞用法07-26
考研英語語法分詞作狀語用法10-20
高中英語語法常用動詞09-23
as用法10-12
the用法歸納10-15
see的用法06-12
have的用法06-26
考研英語It的用法08-03
結婚對聯的用法09-26