数词及其用法ppt课件

1、数词及其用法数词及其用法1;.2数词的分类数词的分类: 主要分为基数词和序数词主要分为基数词和序数词v表示数目多少的数词叫基数词表示数目多少的数词叫基数词v表示顺序的数词叫序数词表示顺序的数词叫序数词3基数词基数词:vA从1-10 one，two，three，four，five，six，seven，eight，nine，tenvB从 11-19 eleven，twelve， thirteen， fourteen， fifteen， sixteen， seventeen，eighteen， nineteen这里除 eleven， twelve， thirteen， fifteen， eighte

2、en为特殊形式外 ,其余都是由其个位数形式后添加后缀-teen构成 .4vC从 21-99 整数几十中除twenty，thirty, forty，fifty，eighty为特殊形式外，sixty，seventy，ninety都是其个位数形式后添加后缀-ty构成。表示几十几时，在几十和个位基数词数词形式之间添加连字符- 21 twenty-one 76 seventy-six vD百位数 个数基数词数词后加“hundred”，表示几百;在几十几与百位间加上and 200 two hundred 101 a/one hundred and one , 320 three hundred and t

3、wenty , 648 six hundred and forty-eight 5E千位数以上千位数以上 v从数字的右端向左端数起，每三位数加一个逗号“，”。从右开始，第一个“，”前的数字后添加 thousand，第二个“，”前面的数字后添加 million，第三个“，”前的数字后添加 billion ,然后一节一节分别表示。 two thousand six hundred and forty-eight sixteen million two hundred and fifty thousand sixty-four five billion，two hundred and thirty-

4、seven million，one hundred and sixty-six thousand，two hundred and thirty-four 2,64816,250,0645,237,166,2346v基数词一般是单数形式，但下列情况，常用复数：vdozen(12)、score(20)、hundred、thousand、million 、billion等在表确切的数字时只用单数形式，但是在表示不确切数字时要用复数，且与of 短语连用。如： 确数: two dozen eggs, three score days, six thousand people 概数: hundreds o

5、f , dozens of , thousands of, 叠用: tens of thousands of, hundreds of thousands of, thousands and thousands of 7b.在一些固定的词组里；如：They arrived in twos and threes. 他们三三两两的到达了。 sixes and sevens 乱七八糟c. 表示几十岁；in ones thirtiesd. 表示年代，用 in +the +数词复数；in the 1980se. 在乘法运算的一种表示法里，如：3 x 5 = 15 Three fives is (are)

6、 fifteen.8基数词数词的句法功能 基数词数词在句中可作主语、宾语、定语、表语、同位语1.The two happily opened the box 2.I need three altogether 3.Four students are playing volleyball outside.4.We are sixteen 5.They three tried to finish the task before sunset(作主语）作主语）（作宾语）（作宾语）（作定语）（作定语）（作同（作同 位语）位语）（作表语）（作表语）9序数词的主要形式序数词的主要形式： vA从第一至第十九

7、 one- first， two- second， three- third， five- fifth，eight-eighth，nine-ninth，twelve- twelfth为特殊形式，其它的序数词数词都是由其相对应的基数词数词后面添加“th”构成。例如： six- sixth、nineteen- nineteenthvB从第二十至第九十九 整数第几十的形式由其对应的基数词数词改变结尾字母y为i，再加“eth”构成。 twentytwentieth thirtythirtieth 表示第几十几时，用几十的基数词数词形式加上连字符“”和个位序数词数词形式一起表示 thirty-first

8、 第三十一 fifty-sixth 第五十六 seventy-third 第七十三 ninety-ninth 第九十九 10vC第一百以上的多位序数词数词 由基数词数词的形式变结尾部分为序数词数词形式来表示。 one hundredth第一百 one hundred and twenty-first 第一百二十一 one thousand，three hundred and twentieth 第一千三百二十 vD序数词数词的缩写形式有时，序数词数词可以用缩写形式来表示。主要缩写形式有。first-lst second-2nd third-3rd fourth-4th sixth-6th tw

9、entieth-20th twenty-third- 23rd 其中lst，2nd，3rd为特殊形式，其它的都是阿拉伯数字后加上th 11v序数词数词在使用时，通常前面要加定冠词 the；但是如果序数词数词前出现不定冠词a或an时，则表示再-，又-。 Well go over it a second time Weve tried it three timesMust we try it a fourth time? v表示日期用序数词数词May 5 五月五日（读作May fifth）,也可以表示为the fifth（5th）of May 12序数词的句法功能序数词的句法功能v序数词数词在句中

10、可作主语、宾语、定语和表语。 The second is what I really need He choose the second We are to carry out the first plan She is the second in our class（作主语）（作主语）（作宾语）（作宾语）（作定语）（作定语） （作表语）（作表语） 13序号表示法序号表示法（1）单纯的序号，可在基数词前加number, 简写为No.。如：No.1第一号（2）事物名词的序号表达法有所不同：v对于一些小序号用序数词也可用基数词表达，v形式分别为：the +序数词 + 名词；名词 + 基数词。如：t

11、he First World War或World War One, Lesson 8 =the eighth lessonv对于一些大序号我们通常只用一种表达法，v 即名词 + 基数词。v如：Room 501, Bus 538。v可用a / the + number + 基数词 + 名词。v如：a No.5 busv the No.8 bus14分数表示法v分数是由基数词数词和序数词数词一起来表示的。 基数词数词作分子，序数词数词作分母， 3/4 three fourths或 three quarters 1/3 one third或a third 24/25 twenty-four twen

12、ty-fifths 1/4 one quarter或a quarter 1/2 a half 1 1/2 one and a half 3 1/4 three and one fourth或 three and one quarter 15v百分数用基数percent表示 50 fifty percent3 three percentv分数和百分数后面不能直接接名词或代词，而用以下形式： 分数/百分数 of + the /these/those/my+ 名词 / 代词, 其谓语动词与of后的名词在人称和数上保持一致，如：Two-thirds of the money was spent on

13、food.Seventy percent of the earth surface is covered by water. One third of the students are from the town.16分数的其它表达形式分数的其它表达形式：v分子与分母之间加in, 分子在前，分母在后，分子分母都用基数词。 如：one in ten 十分之一， five in eight八分之五。v分子与分母之间加out of , 分子在前，分母在后，分子分母都用基数词。 如：one out of ten十分之一， five out of eight八分之五17小数表示法小数表示法 v小数用基数

14、词数词来表示，以小数点为界，小数点左首的数字为一个单位，表示整数，数字合起来读；小数点右首的数字为一个单位，表示小数，数字分开来读；小数点读作 point，o读作 zero或o，整数部分为零时，可以省略不读. 0.4 zero point four或point four 零点四 10.23 ten point two three 十点二三 25.67 twenty-five point six seven 二十五点 六七 l.03 one point o three 一点零三 18倍数的表达方式 once, twice, three times, four times（1）倍数+as + 形容

15、词 / 副词（原级）+ as+比较对象。 如：They have three times as many cows as we do.（2）倍数+形容词或副词的比较级+ than +比较对象 或by + 倍数用在比较级之后。如： This rope is four times longer than that one. They produced more products in 2001 than those in 2000 by twice. The production of grain has been increased by four times this year.（3）倍数用在

16、表示度量名词前，其基本结构为：倍数 + the +size / length / weight + of + 表示比较对象的名词， This room is three times the size of that one. (4)也可用于倍数 + what引导的从句中。如： The college is twice what it was 5 years age.19大约数的表示方法大约数的表示方法（1）用ten、dozen、score、hundred、thousand、million等数词的复数后加of短语来表示几十、几百、上千、成千上万等大约数概念。（2）用less than、under

17、、below、almost、nearly、up to 等来表示小于或接近某数目。 He is good at English, so he can finish the paper in less than two hours.（3）用more than、over、above、beyond、or more等来表示超 过或多于某个数目。如： Peking University has a history of more than 100 years.（4）用or、or so、about、around、some、more or less等表示在某一数目左右。 About 50 people wer

18、e present at that time. （5）用to、from to、between and表示介于两数词。如： His salary rises from 20 dollars a week to 35 dollars a week.20加减乘除表示法v1. 加用plus，and或add表示；等于用is，make，equal等词表示。2+3=? 可表示为： How much is two plus three? 2+3=5 Two plus three is five Two and three is equal to five Two and three make five Two

19、 added to three equals five If we add two to/and three, we get five 21v2. 减用 minus或 take from表示 106?How much is ten minus six? 10-6=4 Ten minus six is four Take six from ten and the remainder is four. Six (taken) from ten is four 十减去六等于四 22v3. “乘”用time（动词）或multiply表示 3X4? How much is three times fou

20、r? 3X4=12 Three times four is/are twelve Three fours is/are twelve Multiply three by four，and we get twelve Three multiplied by four makes twelve 三乘以四等于十二 23v4. “除”用divide的过去分词形式表示 164=? How much is sixteen divided by four? 1644 Sixteen divided by four is four Sixteen divided by four equals/gives/ma

21、kes four If you divide 16 by 4, you get 4. 十六除以四等于四。 24252627281._ people in the world are sending information by E-mail every day.A.Several million B.Many millionsC.Several millions D.Many million2. The number of people invited _ fifty, but a number of them _ absent for different reasons. A.were ;

22、was B.was ; was C.was ; were D.were ; wereA/DC293. Shortly after the accident, two _ police were sent to the sport to keep order. A. dozens of B. dozens C. dozen D. dozen of 4. _ of the land in that district_ covered with trees and grass. A. Two fifth; is B. Two fifth; are C. Two fifths; is D. Two f

23、ifths; are5. It is said that the mountain is about _ high, through which the peasants dug a hole _ deep.A. 400 foot/six hundreds metresB. 400 foots/six hundred metresC. 400 feets/six - hundred - metreD. 400 feet/six- hundred metresCCD306. _ cave that George has discovered in his lifetime is near the

24、 Alps. A. The hundredth B. The hundred C. Hundredth D. A hundredth7. The hero of the story is an artist in his _. A. thirtieth B. thirty C. thirtys D. thirties8. I have to write a _ composition every other week. A. two - thousand - word B. two - thousands - word C. two - thousand - words D. two - thousands - wordsADA31 9.The Yellow River is _ river in China. Hainan is _ island.A. second longe