2011高考英语语法考点专题讲练：代词和数词

　　7.it的用法

　　①用作人称代词,代替前文提到的事情。

　　This bike is not mine. It’s Peter’s.

　　②用以代替提示代词this, that

　　—What is this? —It’s a pen.

　　—Whose book is that? —It’s Mike’s.

　　③起指示代词的作用,指一个人或事物

　　—Who is knocking at the door? —It’s me.

　　—Who is making such a noise. —It must be the children.

　　④指环境情况等。

　　It was very quiet at the moment.

　　⑤指时间，季节，天气，气候等

　　—What time is it? —It is eight o’clock.

　　It often rains in summer.

　　⑥指距离

　　It is five kilometers from the office to my home.

　　It is a long way to the factory.

　　⑦作形式主语和形式宾语

　　当动词不定式,动名词或从句作主语时,通常把它们放在谓语之后,而用it作句子的形式主语

　　It is not easy to finish the work in two days.

　　It is not a good habit to stay up late.

　　It is no use crying over split milk.

　　It is a pity that you didn’t read the book..

　　当复合宾语中的宾语是不定式,动名词,宾语从句时,往往把宾语放在它的补足语后面,而用it作形式宾语,放在宾语补足语之前

　　I think it no use arguing with him.

　　I found it very interesting to study English.

　　He made it clear that he was not interested in this subject.

　　注意：see to it that…(务必)和take it for granted that…(想当然)句型中的it，以及词组make it

　　中的it(做事成功，搞定)。

　　⑧用于强调结构(详见专题九)

　　要强调句子的某一部分(通常是主语,状语,宾语), 可以把it 当作先行词.这种句子的结构是 “It is(was)+被强调部分+that (who )+句子的其余部分” .如果强调的部分是人,可用who whom 代替that

　　I met an old friend in the park yesterday.

　　此句各部分被强调后句型如下：

　　It was I who /that met an old friend in the park yesterday.

　　It was an old friend who/ that/whom I met in the park yesterday.

　　It was in the park that I met an old friend yesterday.

　　It was yesterday that I met an old friend in the park.

　　(二)数词

　　数词分两类：基数词和序数词

　　I.基数词:表示数目的词为基数词。其表达式：

　　1.21-99的两位数，在十位数和个位数之间加连字符构成。如：fifty- three (53)

　　2.101-999的三位数由hundred加and再加两位数或末位数。

　　three hundred and twenty-five (325)

　　3.基数词hundred，thousand，million，billion表示确切数目时不能加s

　　five thousand students (五千个学生)

　　但在表示不确切数目时，要用复数形式，如：hundreds of/thousands of students(许多学生)

　　4.dozen和score的复数形式应注意以下几点：

　　①dozen表示：一打，十二个，score表示：二十;

　　②当dozen与数词，或many，several等连用时，不加“s”，所修饰的名词前常省去“of’;score则不然。

　　two dozen pencils两打铅笔

　　two score of pencils四十支铅笔

　　dozens of people=scores of people许多人

　　③当后面的名词前有"these"，“those"，“them"，" us"等词时, dozen后应加"of "。

　　a dozen of these people

　　two dozen of them

　　three score and ten people中不加of(七十人)

　　II.序数词：表示顺序的数词为序数词。其表达式：

　　1.序数词一般由基数词后+th构成，前面一般加定冠词the，表示“第几”

　　the two hundredth，the eighteenth

　　加不定冠词，则意为“又一,再一”.

　　I like the film very much, so I want to see it a second time.

　　2.以ty结尾的基数词构成序数词时，先把y改成i，再加eth。如：the twentieth，the fiftieth

　　3.不规则的序数词有以下几个：first，second，third，fifth，eighth，ninth，twelfth

　　4.“二十”以上的多位数，个位数用序数词，其余仍用基数词。

　　ninety-third one hundred and forty-ninth

　　5.基数词与序数词连用时，通常是序数词在前

　　the first two pages of the book(这本书的前两页)