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2022年高考英语语法知识梳理--数词数词的分类一、基数词一、基数词1.基数词的形式（1）数词1—10（2）数词11—20（3）数词21—30（4）整数数词10—90（5）百，千，万【提示】单词拼写：4 four，14 fourteen，40 forty。
2.基数词的表达（1）21—99在十位数和个位数之间加连字符构成。
21 twenty-one，36 thirty-six，45 forty-five，73 seventy-three，88 eighty-eight，99 ninety-nine（2）101—999先说“几百”，后接and，再加末尾两位数（或末位数）。
101 one hundred and one，530 five hundred and thirty，（3）1000以上的基数词先从右至左数，每三位数加一个逗号。
9，800 nine thousand，eight hundred60，200，000 sixty million，two hundred thousand（4）hundred，thousand，million，billion等词和具体数字连用时用单数形式。
1，600 one thousand and six hundred6，100 six thousand and one hundred（5）数词的泛指tens of 数十hundreds of 数百tens of hundreds of 数千 a few hundreds of 上百hundreds of hundreds of 成百成百的thousands of 数千tens of thousands of 数万several thousands of 上千thousands of thousands of 成千成千的millions of 数百万several thousands of birds 数千只鸟many millions of citizens 数百万市民tens of thousands of people 成千上万的人3.基数词的用法（1）基数词单数表示确指。
中学英语语法数词表示数目多少或顺序先后的词叫做数词(numeral)。
数词与不定代词很相似，其用法相当于名词与形容词。
数词有两种。
表示数目多少的数词叫做基数词(cardinal numberal), 如one, ten, fifty-two等。
表示顺序先后的数词叫做序数词(ordinal numeral), 如first, tenth, fiftieth等。
(一)基数词1)1-12的基数词是：one 1 seven 7two 2 eight 8three 3 nine 9four 4 ten 10five 5 eleven 11six 6 twelve 1213-19，皆由3-9加后缀-teen构成，即：thirteen 13 seventeen 17fourteen 14 eighteen 18fifteen 15 nineteen 19sixteen 16 (注意：thirteen, fifteen, eighteen的拼法)20-90等十位数均由2-9加后缀-ty构成，即：twenty 20 thirty 30forty 40 seventy 70fifty 50 eighty 80sixty 60 ninety 90(注意：twenty, thirty, forty, fifty, eighty的拼法)21-29由十位数20加个位数1-9构成，中间须有连字符“-”，即：twenty-one 21 twenty-six 26twenty-two 22 twenty-seven 27twenty-three 23 twenty-eight 28twenty-four 24 twenty-nine 29twenty-five 25其它的十位数照此类推，如：thirty-one 31 seventy-five 75forty-two 42 eighty-six 86fifty-three 53 ninety-seven 97sixty-four 642)百位数由1-9加hundred构成，如包含十位数及个位数，中间用and连接，也可以不用；如只包含个位数，即十位数为零时，则and不可省。
高考英语数词知识点复习数词在英语中起着非常重要的作用，它们用来表示数量、顺序和比例等概念。
在高考英语考试中，数词经常出现，掌握数词的用法和规则是提高得分的关键之一。
本文将系统地回顾数词的知识点，帮助大家在高考中取得好成绩。
1. 基数词（Cardinal Numbers）基数词用来表示具体的数量，如1、2、3、10、100等。
在英语中，基数词的表达方式有一些规律可循。
1.1 0-19的基数词对于0-19的基数词，一般采用单词的方式表示，如one（1）、two （2）、three（3）、four（4）等。
需要注意的是，其中11-19的基数词是以“-teen”结尾，如eleven（11）、twelve（12）、thirteen（13）等。
1.2 20-90的基数词20-90的基数词的表达方式与中文类似，采用十位数和个位数的组合。
例如，twenty（20）、thirty（30）、forty（40）、fifty（50）、sixty（60）、seventy（70）、eighty（80）、ninety（90）。
需要特别注意的是，当十位数后接个位数时，一般使用连字符“-”将两个数字连接起来，如twenty-one（21）、thirty-eight（38）等。
1.3 基数词的变形和数词词组有一些基数词在特定情况下需要进行变形。
例如：- 1变为序数词“first”；- 2变为序数词“second”；- 3变为序数词“third”；- 5变为序数词“fifth”。
此外，还有一些表示特定数量的数词词组，如“a half”（一半）、“a quarter”（四分之一）、“a dozen”（一打）、“a couple of”（几个）等。
2. 序数词（Ordinal Numbers）与基数词不同，序数词用来表示顺序、次序和阶级等概念。
在英语中，序数词的构成方式和用法有一些规则。
2.1 构成方式大部分的序数词是在基数词的基础上加上后缀“-th”构成的，如first （第一）、second（第二）、third（第三）、fourth（第四）等。
20÷4＝5：Twenty divided by four is five.Four into twenty goes five.（七）. 约数、不定数量词“多”的表示法列表约数表示法列表含义英语表达例句大于某数more than He has lived here for more than twenty years.over she is over fifty.or more There' re thirty people or more in the meeting-room.小于某数less than I have less than (not more than )fifty dollars.under Children under seven are not allowed to enter.below He would not sell it for below a hundred fifty dollars.or less The coat might cost him sixty dollars or less.大约（某数）nearly She is nearly fifty now.almost Its almost three o'clock.up to Up to ten men c an sleep in this tent.or He spent four or five days writing the article.or so The distance is twenty miles or so.about I visited that village about three years ago.some Their team has some four or five players.more or less The container can hold more or less twenty pounds of water.around/round Let's make it round/around eight o'clock.不定数量词“多”的表示法列表被修饰名词的数英语表达汉译修饰可数名词几十、许多修饰不可数名词许多、大量31.It is not rare in ___that people in ____fifties are going to university for further education.A.90s,theB. the 90s, /C.90s, theirD. the 90s, their32.-Have you seen many sheep in the distance ? -Yes, ___.A. thousand of themB. two thousands of themC. two thousand of themD. two thousand them5．A 这里"first"有人说起副词作用，可以看成表语，也可以看做一种"取得第一名"的习惯用法。
【高考复习】2021高考英语语法：数词数词<例句>There were millions of blooms.有数以百万计的花。
<语法分析>基数词在句子中作主语，此外还可作定语、表语、同位语以及宾语或介词宾语等。
序数词在句中可作定语、表语、主语、宾语或介词宾语等，序数词还可用在某些短语中。
分数词由基数词和序数词构成，基数词代表分子，序数词代表分母，除了分子为1的情况外，序数词都要用复数形式。
分数词可以作主语、定语、状语、宾语或介词宾语等。
<触类旁通>(1) The river is about eighty miles long.这条河约有八十英里长。
语法分析：基数词在句子中作定语。
(2) I read five of his novels.我看了五本他写的小说。
语法分析：基数词作宾语。
(3) Its population is nearly three million.它的人口数量接近三百万。
语法分析：基数词作表语。
(4) She's getting married a third time.她将第三次结婚。
语法分析：序数词和a连用，表示“再一个”、“又一个”等。
(5) I thought that performance third-rate.我认为那场演出是三流的。
语法分析：序数词可用在许多短语中。
(6) Mother divided the cake into thirds.妈妈把蛋糕分成三份。
语法分析：分数词作宾语或介词宾语。
<巩固练习>(1) There are _____[million] of books in that library.(2) Tens of ______[thousand] of mossbacks used to roam the prairie.(3) They arrived in twos and _____[three].(4) A _____[two] swan flew down. Then a third and a fourth.(5) I bought a _____ hand car.(6) She died in her _____[fifty].<参考答案>(1) millions (2) thousands (3) threes (4) second (5) second (6) fifties感谢您的阅读，祝您生活愉快。
语法复习十八：数词高考重点要求：1．掌握基数词、序数词、分数词、倍数、百分数、年月日、钟点、年龄、序号的基本用法。
2．掌握不定数量词、约数词的表达方法。
数词在各个题项中，单选、阅读、听力、写作中发挥着很强的作用，往往用以说明事实的精确性和可信性。
数词是由两大部分构成的即基数词和序数词，而其他数字表示法如分数，小数等均由这两大部分的不同组合而构成。
（三）数词的用法：1.英语中年月日、点钟、序数词、分数词、算式列表示例英语表示法2001．6．30 June 30,2001 30June,2001 30thJune, 20017：25 seven twenty-five twenty-five past even12:54 twelve fifty four six to one9:15 nine fifteen a quarter past nine1031042:30two thirty half past two 21:50twenty-one fifty 9:50p.m. 第21twenty-first 第123 one hundred and twenty-third21 a half 52 2two and two-fifths 20% 20 per cent 20 percent第七路公共汽车 Bus Number Seven第201房间 Room 201人民路153号 153 Renmin Road4+8 =12 Four plus eight is twelve11-7=4 Eleven minus seven is four.6×5=30 Six times five is thirty.20÷5=4 twenty divided by five is four.A ＞B A is more than B.A ＜B A is less than B.A ≈B A is approximately (近似地, 大约)equals to B.A ≠B A is not equal to B.2.约数表示法列表含义 英语表达 例句大于某数 more than He has lived here for more than twenty years.over she is over fifty.or more There're thirty people or more in the meeting-room. 小于某数 less than I have less than (not more than )fifty dollars.under Children under seven are not allowed to enter.below He would not sell it for below a hundred fifty dollars. or less The coat might cost him sixty dollars or less.大约（某数） nearly She is nearly fifty now.almost Its almost three o'clock.up to Up to ten men can sleep in this tent.or He spent four or five days writing the article.or so The distance is twenty miles or so.about I visited that village about three years ago.some Their team has some four or five players.more or less The container can hold more or less twenty pounds of water. around/round Let's make it round/around eight o'clock.3.不定数量词“多”的表示法列表被修饰名词的数英语表达汉译修饰可数名词dozens of 几十、许多scores of 许多many, a good(great) many, many a (饰单数可数名词) 许多、大量hundreds of 数以百计thousands of ,thousands upon thousands of 成千上万millions of 数百万billions of 亿万修饰不可数名词much , a great (good)deal of ,a large amount of ,large amounts of许多、大量修饰可数名词或不可数名词a lot of /lots of ,plenty of, a large quantity of ,large quantities of许多、大量练习、数词1. Two __died of cold last winter.A. hundreds old peopleB. hundred old peopleC. hundreds old peoplesD. hundred old peoples2. He was only in__ at the time.A. his 20'sB. the 20'sC. his twentiesD. the twenties3. The two great men wrote those letters in__ .A. 1870'sB. 1879sC. the 1870'sD. the 18704. I wonder if I can ask him__ time.A. fourB. fourthC. the fourthD. a fourth5. He came out__ in the track events.A. firstB. oneC. the firstD. the one6. It was in 1939 that __broke out.A. World War SecondB. the World War SecondC. Second World WarD. World War II7. You'll have to spend __writing your report here.A. one day or two daysB. one day or twoC. a day or twoD. two days or one8. He cut the cake__ .A. in halvesB. in halfC. into halvesD. into half9. The earth is nearly__ the moon.A. 50 time the size ofB. 50 times the size ofC. 50 times as size asD.50 times as that of10. Either you or the headmaster __the prizes for these gifted students at the meeting.105A. is handing inB. are to hand outC. are handing inD. is to hand out11. __of the population here are peasants.A. 20 percentsB. 20 percentC. the 20 percentD. the 20 percents12. It's about__ , the thickness of a human hair.A. two-fifteenthB. two-fifteenthsC. two fifteenD. two fifteens13. The price of such material was reduced__ .A. by 18 percentB. to 18 percentC. at 18 percentD. for 18 percent14. South of the equator, 81 percent of the surface of the earth__ water.A. isB. areC. wasD. were15. They sold __boxes of such sweets last week.A. four dozenB. four dozensC. four dozens ofD. four dozen of16. It took me __ days to finish drawing a beautiful horse.A. a half dozenB. half a dozenC. haft dozensD. half dozen17.__people were sent there to help fight against the flood.A. Three scores ofB. Three score ofC. Three scoreD. Three scores18. Don't leave you work,__ .A. done halfB. half doneC. a half doneD. done a half19. Nobody can do two things well __ .A. at one timeB. at onceC. one timeD. once20. He has__ books in his study.A. several thousandsB. some thousands ofC. some thousandsD. some thousand of21. On National day__ people take part in all kinds of celebration.A. hundreds of millions ofB. millions of hundred ofC. hundreds millions ofD. millions hundreds of22. He has lived at__ for 30 years.A. No. 101 Heping StreetB. 101 Heping StreetC. Heping Street 101D. Heping street No. 10123. You can find him in__ .A. Room 201B.201 RoomC. the Room 20D. the 201 Room24. It's__ walk from here to my school.A. two - hoursB. two hoursC. two - hourD. a two - hour25. It was in__ when he was already in ___ that he went to Yan'an.A. the 1940s, the 40sB. the 1940s, his fortiesC. 1940's, his fortiesD. the 1940's, his 40s26. He went to the market and bought __eggs and some meat.A. three dozen ofB. three dozenC. three dozensD. three dozens of27.Shortly after the accident two ___police were sent to the spot to keep order.106A. dozen ofB. dozensC. dozenD. dozens of (MET92 29)28.Mr Smith ___me to buy several __eggs for the dinner.A. asked, dozenB. suggested, dozens ofC. had, dozenD. persuaded, dozens of ('94上海)29.____of the land in that district ___covered with trees and grass.A. Two fifth, isB. Two fifth, areC. Two fifths , isD. Two fifths, are (2000上海)30.Two ___died of cold last winter.A. hundreds old peopleB. hundred old peopleC. hundred old peoplesD. hundred old peoples ('88MET.15)31.It is not rare in ___that people in ____fifties are going to university for further education.A.90s,theB. the 90s, /C.90s, theirD. the 90s, their ('99上海 6)32.-Have you seen many sheep in the distance ? -Yes, ___.A. thousand of themB. two thousands of themC. two thousand of themD. two thousand them语法复习十八：数词1．B2. C 表示"几十"的数字的复数与所有格代词一起来用以表示人的年龄，本句为"二十多岁"。
语法复习十八：数词高考重点要求：1．掌握基数词、序数词、分数词、倍数、百分数、年月日、钟点、年龄、序号的基本用法。
2．掌握不定数量词、约数词的表达方法。
数词在各个题项中，单选、阅读、听力、写作中发挥着很强的作用，往往用以说明事实的精确性和可信性。
数词是由两大部分构成的即基数词和序数词，而其他数字表示法如分数，小数等均由这两大部分的不同组合而构成。
（一）基数词：表示数目的词为基数词，它的构成如下表：（二）序数词：表示顺序的数词为序数词，它的构成如下表：（三）数词的用法：1.英语中年月日、点钟、序数词、分数词、算式列表示例 英语表示法2001．6．30 June 30,2001 30June,2001 30thJune, 2001 7：25 seven twenty-five twenty-five past even 12:54 twelve fifty four six to one 9:15 nine fifteen a quarter past nine 2:30 two thirty half past two 21:50 twenty-one fifty 9:50p.m. 第21 twenty-first第123one hundred and twenty-third 21a half522two and two-fifths 20%20 per cent 20 percent第七路公共汽车 Bus Number Seven 第201房间 Room 201 人民路153号 153 Renmin Road 4+8 =12 Four plus eight is twelve 11-7=4 Eleven minus seven is four. 6×5=30 Six times five is thirty. 20÷5=4 twenty divided by five is four. A ＞B A is more than B. A ＜B A is less than B.A ≈B A is approximately (近似地, 大约)equals to B. A ≠BA is not equal to B.2.约数表示法列表含义英语表达例句大于某数more than He has lived here for more than twenty years.over she is over fifty.or more There're thirty people or more in the meeting-room.小于某数less than I have less than (not more than )fifty dollars.under Children under seven are not allowed to enter.below He would not sell it for below a hundred fifty dollars.or less The coat might cost him sixty dollars or less.大约（某数）nearly She is nearly fifty now.almost Its almost three o'clock.up to Up to ten men can sleep in this tent.or He spent four or five days writing the article.or so The distance is twenty miles or so.about I visited that village about three years ago.some Their team has some four or five players.more or less The container can hold more or less twenty pounds of water.around/round Let's make it round/around eight o'clock.3.不定数量词“多”的表示法列表被修饰名词的数英语表达汉译修饰可数名词dozens of 几十、许多scores of 许多many, a good(great) many, many a (饰单数可数名词) 许多、大量hundreds of 数以百计thousands of ,thousands upon thousands of 成千上万millions of 数百万billions of 亿万much , a great (good)deal of ,修饰不可数名词许多、大量a large amount of ,large amounts ofa lot of /lots of ,plenty of, a large quantity of ,修饰可数名词或不可数名词许多、大量large quantities of练习、数词1. Two __died of cold last winter.A. hundreds old peopleB. hundred old peopleC. hundreds old peoplesD. hundred old peoples2. He was only in__ at the time.A. his 20'sB. the 20'sC. his twentiesD. the twenties3. The two great men wrote those letters in__ .A. 1870'sB. 1879sC. the 1870'sD. the 18704. I wonder if I can ask him__ time.A. fourB. fourthC. the fourthD. a fourth5. He came out__ in the track events.A. firstB. oneC. the firstD. the one6. It was in 1939 that __broke out.A. World War SecondB. the World War SecondC. Second World WarD. World War II7. You'll have to spend __writing your report here.A. one day or two daysB. one day or twoC. a day or twoD. two days or one8. He cut the cake__ .A. in halvesB. in halfC. into halvesD. into half9. The earth is nearly__ the moon.A. 50 time the size ofB. 50 times the size ofC. 50 times as size asD. 50 times as that of10. Either you or the headmaster __the prizes for these gifted students at the meeting.A. is handing inB. are to hand outC. are handing inD. is to hand out11. __of the population here are peasants.A. 20 percentsB. 20 percentC. the 20 percentD. the 20 percents12. It's about__ , the thickness of a human hair.A. two-fifteenthB. two-fifteenthsC. two fifteenD. two fifteens13. The price of such material was reduced__ .A. by 18 percentB. to 18 percentC. at 18 percentD. for 18 percent14. South of the equator, 81 percent of the surface of the earth__ water.A. isB. areC. wasD. were15. They sold __boxes of such sweets last week.A. four dozenB. four dozensC. four dozens ofD. four dozen of16. It took me __ days to finish drawing a beautiful horse.A. a half dozenB. half a dozenC. haft dozensD. half dozen17.__people were sent there to help fight against the flood.A. Three scores ofB. Three score ofC. Three scoreD. Three scores18. Don't leave you work,__ .A. done halfB. half doneC. a half doneD. done a half19. Nobody can do two things well __ .A. at one timeB. at onceC. one timeD. once20. He has__ books in his study.A. several thousandsB. some thousands ofC. some thousandsD. some thousand of21. On National day__ people take part in all kinds of celebration.A. hundreds of millions ofB. millions of hundred ofC. hundreds millions ofD. millions hundreds of22. He has lived at__ for 30 years.A. No. 101 Heping StreetB. 101 Heping StreetC. Heping Street 101D. Heping street No. 10123. You can find him in__ .A. Room 201B.201 RoomC. the Room 20D. the 201 Room24. It's__ walk from here to my school.A. two - hoursB. two hoursC. two - hourD. a two - hour25. It was in__ when he was already in ___ that he went to Yan'an.A. the 1940s, the 40sB. the 1940s, his fortiesC. 1940's, his fortiesD. the 1940's, his 40s26. He went to the market and bought __eggs and some meat.A. three dozen ofB. three dozenC. three dozensD. three dozens of27.Shortly after the accident two ___police were sent to the spot to keep order.A. dozen ofB. dozensC. dozenD. dozens of (MET92 29)28.Mr Smith ___me to buy several __eggs for the dinner.A. asked, dozenB. suggested, dozens ofC. had, dozenD. persuaded, dozens of ('94上海)29.____of the land in that district ___covered with trees and grass.A. Two fifth, isB. Two fifth, areC. Two fifths , isD. Two fifths, are (2000上海)30.Two ___died of cold last winter.A. hundreds old peopleB. hundred old peopleC. hundred old peoplesD. hundred old peoples ('88MET.15)31.It is not rare in ___that people in ____fifties are going to university for further education.A.90s,theB. the 90s, /C.90s, theirD. the 90s, their ('99上海6)32.-Have you seen many sheep in the distance ? -Yes, ___.A. thousand of themB. two thousands of themC. two thousand of themD. two thousand them。
版权所有：中华资源库 www.ziyuanku.com 四. 数 词 一.数词的定义 数词是表示数目多少或先后顺序的词,有基数词和序数词两种。表数量的数词叫基数词，如one, two, three。表顺序的数词叫序数词，如first, second, third, fourth, fifth,...
二.基数词 （一）构成 1）1~12单独记 one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve 2)13~19词尾为-teen：thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen 3)20~90逢整十词尾为-ty：twenty, thirty,forty,fifity,... 4)21~ 99在十位数和个位数之间加连字符构成，如： 73 seventy-three, 88 eighty-eight 5)101~ 999先说几百，再加and,再加末尾两位数，如： 178 one hundred and seventy-eight 6)1000以上的数词，先从后向前数，每三位用一个数逗点“，”隔开。第一个“，”是thousand千，第二个“，”是million百万，第三个“，”是billion美语中的十亿（英国用thousand million），然后一节一节地用几百几十几的方法来数。 注意 ①英语中没有“万”，用ten thousand 10,000表示 ②十万的表示法：one hundred thousand 100,000 ③百万的表示方法：a/one million 1,000,000 ④千万及以上的表示法： 2百亿 twenty thousand million（英），twenty billion（美） 万亿，兆a trillion=a million million =1012,(旧指-尤英国，百万兆，1018) （二）基数词的使用 基数词可在句中作主语、表语、定语、状语、介宾、同位语。 Two of them are students.主语 Two and two are four. 表语 We two joined the army.同位语 Two thousand people were present at the meeting.定语
（三）基数词使用的注意事项 1）hundred, thousand, million, billion, score(20),dozen(12)前有数词表示具体数目时，这些词不加复数。当前无数词时，这些数词要加复数后再加of 连接名词，来表示不具体量。 如：five hundred people, two score apples, hundreds of people, scores of pears, thousands of, thousands and thousands of, tens of thousands of, millions of, a few hundred men, many thousands of men, some/several million(s of) men 2)表示“几十”的数词的复数形式前用形容词性物主代词修饰可用来表示“在某人„十几岁时”；用定冠词修饰表示“„年代”。 in one's early twenties(thirties)在某人二十（三十）几岁时 版权所有：中华资源库 www.ziyuanku.com
the 1840's/the 1840s 19世纪40年代 the 1980s/the 1980’s 20世纪80年代 ▲十亿以上的大数，英美有不同的表示： 英国英语 美国英语 十亿thousand million one billion 百亿ten thousand million ten billion 千亿hundred thousand million one hundred billion 万亿one thousand billion one trillion 年代的读法: 297读作two ninety-seven或two hundred and ninety-seven 1908读作nineteen and eight或nineteen o eight或nineteen hundred and eight 1949读作nineteen forty-nine或nineteen hundred and forty-nine 2000读作two thousand 4)a.在美国英语中，表示几点过几分可用after,表示几点差几分可用before。如:12点10分：ten after twelve。11点50分：ten before twelve。 b.若想表明是上午，可在时间后加上am或a. m.(a.m.是拉丁语ante meridiem的缩写，意为“上午”)，若想表明是下午，可在时间后加上pm或p. m. (p.m.是拉丁语post meridiem的缩写意为“下午”)。a.m.或p. m.前若是整点，用了a. m.或p. m后，不再用o'clock，也不可加 “：00 ”。如：at 8 a. m.（上午8点），at 5 p. m.（下午5点）。 c.表示“„点整”时，用sharp。如: at nine o'clock sharp（九点整），at 23:00 sharp（二十三点整）。 5)年龄表达 ①表示“„岁” He is eighteen (years old). He is aged eighteen. He is at the age of eighteen. His age is eighteen. ②表示“快满„岁” He will be eighteen years old. He is going on eighteen years old. He is getting on for eighteen. It will be his eighteenth birthday. ③表示“不满„岁” He is barely/nearly/almost eighteen. He is not quite/yet eighteen. He is under/below eighteen. ④表示“已经„岁”可用以下方法表示： He is past/over/above eighteen. He is more than eighteen. He has turned eighteen. ⑤表示大概年龄时用“in one's +基数词复数形式”结构。 a.从十三岁到十九岁，用in one's teens . b.二十岁以上就用in one's twenties/thirties/forties/fifties „/nineties，还可以借助early，middle，late来表达得更明确一些。
三.序数词 版权所有：中华资源库 www.ziyuanku.com
1）记忆口诀，基数词变为序数词 一二三要单独记：one-first, two-second, three-third th要从四加起：four-fourth, five-fifth,... eight少个t：eight- eighth nine去掉e：nine-ninth ve用f来代替：five-fifth, twelve-twelfth ty变成tie：twenty-twentieth 表第“几十几”，基数加序数记心里：twenty-one→twenty-first 2)序数词在句中主要作定语，一般情况下序数词前要加定冠词。Monday is the second day of a week. 3)序数词前有时加不定冠词，表示“又一、再一”，相当于another。 Would you like a second cup of tea? I had a fourth apple.我(吃了三个苹果后)又吃了一个苹果。 4）first, second等有时可表示一批人或物。 The first milu deer came from China in the 1860s. 最早的麋鹿是在十九世纪六十年代来自中国的。 5）有时序数词作状语，不加冠词。 He came out first in the contest. 他在比赛中得第一名。 6）first, second等在用来指“冠军、亚军”等获胜名次时也常不加冠词。 He is first.他是冠军。
四.百分数、分数、小数的构成及用法 1)百分数：基数词加百分号％percent: 89%→eight-nine percent 2)分数：分子基数词，分母序数词。分子大于1，分母用复数。分子与分母用连字符连接。 1/3: one third, 2/5: two fifths 3)带分数：基数词 + and +分数表达：5 6/7 : five and six-sevenths 注意 1/2: a half, one half 1/4: one-fourth, one /a quarter 3/4: three quarters 1/3: a third(33.33r %读作 thirty-three point three three recurring percent) 3）小数：小数点读作“point”，数字一律用基数词 1.45: one point four five 4)通常分数、百分数、小数做定语。“分数（百分数）of +名词”作主语时谓语动词是根据名词确定的，名词为单数动词即用单数，名词为复数动词即用复数动词。 50% apples are here. One third apple is eaten. ★one and a half后名词用复数，谓语动词一般用单数，不过事实上也可用复数。
五. 加减乘除运算表达 4 + 4＝8：Four plus/added to four equals eight. Four and four are eight. 7－3＝4： Seven minus three is four. Three from seven leaves four. 8×8＝64：Eight multiplied by eight is sixty -four.
