(完整版)初中英语数词知识点和练习

数词

1.什么叫做数词？

表示数目多少或顺序多少的词叫数词，数词分为基数词和序数词。表示数目多少的数词叫基数词；表示顺序的数词叫序数词。

A．基数词的构成

1）1－12有各自独立的形式。

One，two, three ,four ,five ,six ,seven ,eight ,nine ,ten ,eleven ,twelve

2）13-19都是相对应3－9加上teen构成，thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen,

3）20－90都以-ty结尾，特殊拼写的有

twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety

4）21－99,整数十位数＋各位数，中间有

“－”。

5）百位数，由百位数＋and+两位数组成。

注：1、1000以上几个的词，每三位数加一个逗号，第一个逗号前的数为thousand，第二个逗号前的数为million（百万）, 第三个逗号前的数为billion（十亿），第四个逗号前的数为trillion（万亿）

888，888，888，888

eight hundred and eighty-eight billion, eight hundred and eighty-eight million, eight hundred and eighty-eight thousand, eight hundred and eighty-eight

2、基数词常与名词构成的合成词在句中作定语，中间要用连字符“_”，这个名词只用单数形式．

a two hundred –word report

a seven-day holiday

a 3 –year –old girl

3. 基数词的用法

1、表示一个具体数字时，hundred, thousand,

million，billion一律不用复数；在表示一个不

确定数字时则用复数。例如：

1) Our country has a population of 1,300 million

people.

2) There are three thousand students in our

school.

3) After the war, thousands of people became

homeless.

4) Maize is the most important food crop for

millions of people in the world.

2、在一些表示“一排”或“一组”的词组里；

如：They arrived in twos and threes.

他们三三两两的到达了。

3、表示“……十”的数词的复

数形式可用来表示“几十岁”

或年代，例如：

1）He is in his early thirties．

2）He died still in his forties．

3）This took place in 1930s．

4、表示时刻用基数词。例如：

We get up at six.

The workers begin work at eight.

（1）表示“几点过几分”，用介词past,但须在半小时以内。例如：

ten past ten,

a quarter past nine,

half past twelve

（2）表示“几点差几分”用介词to, 但分数须在半小时以上。例如：twenty to nine,

five to eight,

a quarter to ten

表示“几点几分”还可直接用基数词。例如：

seven fifteen,

eleven thirty,

nine twenty

注意下列习惯表达方式：

half an hour half a kilo

one hour and a half= one and a half hours

two and a half kilos = two kilos and a half

one or two days = one day or two

eighty meters long

one thousand miles away

five meters deep ( wide/ tall/ high/long)

five meters in depth / width/ height/ length

B. 序数词的构成

1）1－3分别为first,second,third 。

2）4－19都是在后面加上th,特殊的有

fifth, eighth, ninth,twelfth。

3）20－90把y变成ie然后加th,如twentieth。

4）21－99的序数词变后面的个位数。

序数词可以用缩写，如1st, 2nd, 3rd ,4th…

序数词的用法

（1）序数词主要用作定语，前面要加定冠词，例如：

The first truck is carrying a food baskets．

John lives on the fifteenth floor．

（2）序数词有时前面可加不定冠词来表示“再一”，“又一”这样的意思，例如：We'll have to do it a second time．

Shall I ask him a third time？