初一数词讲解

数词讲解 (一)数词的概念 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。 (二)基数词的表示法 1.1—12的基数词是独立的单词,即: one,two,three,four,five,six,seven,eight, nine,ten,eleven,twelve。 2.13—19的基数词以-teen结尾。如: fourteen,seventeen等,但13,15,18较特殊, 13—thirteen 15—fifteen 18—eighteen。 3.20—90的整十位均以-ty结尾。如: sixty, ninety,但20,30,40,50,80较特殊, 20—twenty 30—thirty 40—forty 50—fifty 80—eighty。 4.十位数与个位数之间要加连字符号“-”,如:28 twenty-eight,96 ninety-six。 5.百位和十位(若无十位则和个位)之间加and,如:148—one hundred and forty-eight 406—four hundred and six。(108怎么说) 6.hundred(百),thousand(千),million(百万),billion(十亿)等前面即使有具 体的数词,也不能在它们的后面加s。如:600—six hundred,8百万—eight million。 hundred,thousand,million用复数形式修饰名词时要用“of+复数名词”,如:数以百 计的年轻人hundreds of young people;数以千计的书thousands of books。注意:hundreds of /thousands of/millions of +复数名词,其前面不能加具体的数词。 7.1000以上的数字,从后往前数每三位加一个逗号“,”第一个逗号前为千(thousand), 第二个逗号前为百万(million),第三个逗号前为billion(十亿)。英语中无“万”这 个词,我们可以用“几十个千(thousand)”表示几万,“几百个千(thousand)”表示“几 十万”。如:2,510=two thousand five hundred and ten;84,296=eighty-four thousand two hundred and ninety-six;274,350=two hundred and seventy-four thousand three hundred and fifty。翻译成英文的时候,十亿,百万,千之间直接连接,不用and,只有 百和十位或个位之间用and,举例:1,234,567 8.基数词+单数名词+形容词构成合成形容词。如:一个五岁的女孩a five-year-old girl. 女子800米接力girls'800-metre relay race。长河长6,300米 The Changjiang River is 6,300-kilometre-long.(你能用另一种数字表达法来翻译这个句子吗?) (三)序数词的表示法 1. 以下是最基本的序数词:first, second,third, fourth , fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, sixteenth, seventeenth, eighteenth, nineteenth, twentieth, thirtieth, fortieth, fiftieth, sixtieth, seventieth, eightieth, ninetieth. 【说明】①许多序数词是由相应的基数词后加th构成的,如:four / fourth,six / sixth,ten / tenth,sixteen / sixteenth,但是nine变为序数词是ninth,而不是nineth。 ②twentieth, thirtieth, fortieth 等表示整十的序数词,由相应的基数词将词尾y改为ie,再加 th 构成。 1 ③first, second, third 通常可缩写为1st, 2nd, 3rd。凡是以th结尾的序数词可缩写为“基数词+th”:4th, 5th, 9th, 11th, 60th, 128th等。 2. 非整十的多位数,将个位数变成序数词即可:twenty-first(第21),thirty-sixth(第36), ninety-ninth(第99),three hundred and sixty-fifth(第365)等。 3. hundred, thousand, million 等序数词形式为hundredth, thousandth, millionth 4.序数词前使用冠词应注意的两点 a. 序数词前通常要用定冠词 It’s the third time I’ve been here. 这是我第三次来这儿。 The second is better than the first. 第二个比第一个好。 【说明】①表示考试或比赛等的名次时,通常省略定冠词: She was (the) third in the exam. 她考试得了第三名。 ②序数词用作副词时也通常不用冠词: He came first. 他先来。 I’ll have to finish my homework first. 我得先把作业做完。 ③有些习语中的序数词前没有冠词: at first 开始at first sight 乍看起来first of all 首先 ④但若序数词前用了物主代词或名词所有格,则不能再用定冠词: his second wife 他的第二个妻子Tom’s third book 汤姆的第三本书 b. 序数词前有时可用不定冠词,表示次第在原有基础上的增加: A second student stood up. 又一个(第二个)学生站了起来。 I want to read the book a third time. 这本书我想读第三次。 序数词前用定冠词和不定冠词的区别在于,定冠词表特指,不定冠词表泛指, I like the third girl. 我喜欢第三个女孩。(至少有三个女孩供选择,特指) I saw a third girl. 我又看见了第三个女孩。(暗示原来已看见两个,这已是第三个) (四)数词的主要用法 1.时间的数字表达法: ⑴几点钟,用基数词来表示:如:7点钟—it’s seven o’clock.. ⑵表达非整点时间时,用to或者是past. to 表示的是“差,不到” Past表示的是“过,多于”。需要注意的是to 前的时间要小于30分钟,past 前的时间小于、等于30分钟。整半点的时候用half. 例子: 7点过一刻:fifteen past seven /a quarter past seven . 差10分7点钟:ten minuts to seven 7点半: half past seven (3)表示非整点时间的另外一种表达法,与汉语表示法相同: 如八点一刻:at eight fifteen 六点四十五分:at six forty-five (4)half 的用法:half a ( an ) + 名词; a half +名词 如:半个小时:half an hour, 一个半小时:两种说法:one hour and a half; one and a half hours. 2. 年份的数字表达: (1)单独使用年份时:用基数词来表达:如1897:eighteen ninety-seven. 1998—nineteen ninety-eight 读法:个位和十位都是零时,读成hundred: 1900:the year nineteen hundred. 十位是零,读作o : 1908—the year nineteen o eight 百位和十位都是零时,读作thousand: 2008:the year two thousand eight (2)月日年共同使用时:年依然用基数词,日用序数词 1998年10月1日—October the first, nineteen ninety-eight. (3).与介词之间的用法:有具体日子用on , 无日子,只有月、年或只有月,只有年in 例子:在1997年7月1日—on July the first 1998 在90年代— in the 1990s ; 1990年10月—in October 1990 3.表示编号 (1). 单纯的编号,可在基数词前加number,简写为No.。如No.2第二。 (2). 序号与事物名词连用时分三种情况: (A)小序号可用“the +序数词+名词”或“名词+基数词”。如第一次课可以说the First Lesson或Lesson One。 (B)大序号通常只用“名词+数词”。如808号房间Room 808;168路公共汽车Bus No.168;南京路1490号1490 Nanjing Road;电话号码83545601(用基数词逐个念,0念字母O)。 数字1用“a/the + number+基数词+名词”。如a No.3 bus一辆三路公共汽车,the No.3 bus那辆三路公共汽车。 4.表示倍数 (1). 倍数+as +形容词/副词(原级)+ as。如: This bridge is three times as long as that one.这座桥是那座桥的三倍长。 2. 倍数+形容词或副词的比较级+than。如: This bridge is three times longer than that one.这座桥是那座桥的三倍长。 3. 倍数+ the size/length/weight…+of+表示比较对象的名词。如: This bridge is three times the length of that one. 这座桥是那座桥的三倍长。 4. 倍数+what引导的从句。如: The college is twice what it was 5 years ago.这所大学是它五年前的两倍。 5.分数、小数和百分数表示法 (1).分数的分子以基数词表示,分母以序数词表示,当分子大于1时,序数词要用复数,其写法与读法如下: 1/2 — a/one half 1/3 — a/one third 1/4 — a/one fourth; a/one quarter 2/5 — two fifths (2).小数是以基数词加小数点表示,小数点前面的数按基数词的规则读,小数点后面的数按个位基数词依次读出,如: 0.5 — zero point five 0.006 — zero point zero zero six 0.257 — zero point two five seven (3).百分数是由基数词或小数加百分号组成,百分号(%)读作percent,如: 0.6% — zero point six percent 5% — five percent 100% —one hundred percent 12.34% —twelve point three four percent 148.06 — a/one hundred and forty-eight point zero six 习题精选 1.单词百变 (1)Today is his ______(twenty) birthday.(2)Let’s go to see the pandas _____(one) (3)December is the ______ month of the year. (twelve) (4)Today is my friend’s ____ ( nine ) birthday. (5)The________ ( five) lesson(课) is interesting. 2.句型转换 (1)This is Unit One = This is ( )( )( ). (2)This is Bus 107 = This is ( ) ( ) 107 bus (3)His date of birth is on February 20th.=His ( ) is ( ) ( ) (4)It’s seven fifteen.=It’s ( a )()()() (5)It’s eight thirty in Paris.=It’s ()()()in Paris. (6)We only have one shower.(对划线部分提问) (7)今天是11月11号,星期五。It's _____, November_______ today. 3.单项选择 1) There are_________employees and several employers in the company. A) a thousand of B) thousand C) thousands of D) thousands 2) He always wanted to have_________of books and he has recently bought four_________. A) hundreds...hundreds B) hundred...hundred C) hundreds...hundred D) hundred...hundreds 3)His name is Li Dawei. Li is his _________ name ,but Dawei is his_________ name. A first last B last first C first family D family last 4) The assignment for Monday is to write________about your best friend. A) a two hundred word composition B) a two hundred words composition C) a two hundreds words composition D) a two hundreds word composition 5)“How many presidents are there before Abraham Lincoln?”“Fifteen, so he was________” A) the sixteenth president B) the sixteen president C) president sixteen D) president the sixteen 6) Jane Eyre is a good book. I have read it and I decide to read it_________. A) the second time B) a second time C) two time D) two times 7) My new bicycle cost me about_________my old one. A) three times than B) three times as much as C) three times much than D) three times as many as 8) When were you born? I was born_____. A) on July 3rd, 1973 B) in July 3, 1973 C) on July 3, 1973 D) in July 3rd, 1973 9)Yesterday my mother bought_______eggs in the market. Unfortunately, she broke two and ten were left. A) a dozen B) dozens of C) dozen D) several dozens 10) I bought a big fridge, which occupied about_______of the space in my kitchen. A) two five B) two fifth C) second fifth D) two fifths 11.Could you tell us how to read the number 18,306,211? A.eighteen million, three hundred and six thousands, two hundred eleven B.eighteen million, three hundred and six thousand, two hundred and eleven C.eighteen millions, three hundred six thousands, two hundreds and eleven D.eighteen thousand, three hundred and six, two hundred eleven 12.Over ______ of the articles on education have been published。 A.two thirds B.two third C.seconds three D.seconds third 13.My father left home at about __。 A.six thirty B.thirty six C.thirty to six D.six past thirty 6