一、 数词：

分类：数词有基数词和序数词两种。英语的数词可以作句子的主语、宾语、表语和定语。

一）. 基数词：表示数目的词叫基数词。

1、 英语中常用的基数词有：

1 2 3 4 5 6 7 8 9 10 11 12

one two three four five six seven eight nine ten eleven twelve

13 14 15 16 17 18 19

thirteen fourteen fifteen sixteen seventeen eighteen nineteen

20 30 40 50 60 70 80 90 100

twenty thirty forty fifty sixty seventy eighty ninety one(a) hundred

23   35           101

twenty-three   thirty-five           one hundred and one

1000→one(a) thousand,

10000→ ten thousand,

100000→one hundred thousand ,

1000000→one million,10000000→ten million,

100000000→one hundred million,

108→one hundred and eight, 146→one hundred and forty-six,

500→five hundred , 1001→one thousand and one, 1813→one thousand eight hundred and thirteen.

[注意]：

(1)百位与十位之间要加and；十万位和万位,亿位和千万位之间通常也要加and。

(2)英语用千、百万等单位计数,大数字从右向左看, 每隔三位划一逗号,倒数第一个逗号之前要用thousand,倒数第二个逗号之前要用million,倒数第三的逗号之前要用billion表示。

(3) hundred、 thousand、 million作数词时,不用复数,前面可以加上one, two, …等其它数词。用作名词时复数表示“成…上…”,后面必须要有of,前面可以加上some,many,several等词。如：five hundred(五百), hundreds of(成百上千的), ten thousand(一万), thousands of(成千上万的), millions of(成百万的)

一）. 序数词：表示顺序的数词叫序数词。

1、 英语的序数词基本变法：

(1) 一般在基数词后加th,

(2)-ve结尾的改为-fth,

(3)-ty结尾的改为-tieth,

(4)熟记特殊词。

2、序数词如下：

1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th

※first ※second ※third fourth fifth sixth seventh eighth ninth tenth eleventh twelfth

13th 14th 15th 16th 17th 18th 19th

thirteenth fourteenth fifteenth sixteenth seventeenth eighteenth nineteenth

20th 30th 40th 50th 60th 70th 80th 90th 100th

twentieth thirtieth fortieth fiftieth sixtieth seventieth eightieth ninetieth one undredth

21st 22nd 23rd   35th           101st

twenty-first twenty-second twenty-third   thirty-fifth           one hundred and first

1000^th→one thousandth,  1000000^th →one millionth.,

第703→the seven hundred and third,

第5480→the five thousand four hundred and eightieth.

3、注：

(1)两位以上的序数词仅个位数部分用序数词,其余部分仍用基数词。如：thirty-sixth,

(2) 使用序数词时一般加定冠词the. 如：I’m in the third grade.

(3) 序数词作“几分之几”讲时,有复数形式。如：1/5→one fifth ; 2/3→ two thirds ; 4/7→ four sevenths ; 1/2→ a half ; 1/4→a quarter ; 3/4→ three quarters ; 50%→ fifty hundredths ( fifty per cent).

4、数词的用法：

• 表示年份：2002: twenty thousand and two ; 1976 : nineteen seventy-six.
• 表示日期： 12月1日:1st或the first of December；2002年11月8日: Nov. 8th, 2002.
• 表示时刻： 5：15→ five fifteen或a quarter past five ; 8：30→ eight thirty或half past eight ; 10：45→ ten forty-five或a quarter to eleven.
• 表示编号：Room 105→Room one 0 five; Bus No.13→Bus Number Thirteen; P.5→Page Five; Tel.No.7658659→Telephone Number seven-six-five-eight-six-five-nine
• 小数的读法：7→ five point seven,  0.16 →zero point one six.
• 6、“半”的表达： 1/2→half, 半小时→half an hour, 1.5小时→one and a half hours或one hour and a half.
• 序数词前面加the时,表示顺序,加a/an时表示“再一、又一”。如：The third lessonis rather difficult.(第三课相当难)/ Shall we read the text a third time?(我们把课文读第三遍,好吗？)