第四讲 数词专题 学案--高考英语一轮复习.docx

四、数词专题：基数词和序数词1.基数词：描述事物数量的多少。序数词：表示顺序的词。基数词和序数词的拼写和听读是难点。同学们要掌握好！第一组基数词序数词1-10 第1-第10one, two,three,four,five,six,seven,eight,nine,tenfirst,second,third,fourth,fifth,sixth,seventh,eighth,ninth.tenth11-19第11-第19eleven,twelve,thirteen,fourteen,fifteen,sixteen,seventeen,eighteen,nineteeneleventh,twelfth,thirteenth,fourteenth,fifteenthsixteenth,seventeenth,eighteenth,nineteenth20-90第20-第90twenty,thirty,forty,fifty,sixty,seventy,eighty,ninety twentieth, thirtieth,fortieth,fiftieth,sixtieth,seventieth,eightieth,ninetieth¤9基数词 nine，序数词 ninth(去e+th)4,14,40的书写有不同 four, fourteen, forty12 基数词twelve 序数词twelfth20，30，40，50，60，70，80，90基数词 twenty,thirty,forty,fifty,sixty,seventy,eighty,ninety序数词 (把y-i+eth) 分别为:twentieth, thirtieth,fortieth,fiftieth,sixtieth,seventieth,eightieth,ninetieth序数词可以用缩写形式表示，其中1st，2nd，3rd为特殊形式，其它的都是阿拉伯数字后加th.first-1st, second-2nd, third-3rd,fourth-4th,sixth-6th,twentieth-20th,twenty-third-23rd第二组基数词序数词几十几：几十和个位基数词之间添加连字符 第几十几：个位要用序数词中间要加连字符21 twenty-one第21 twenty-first99 ninety-nine第99 ninety-ninth31 thirty-one第31 thirty-first55 fifty-five第55 fifty-five72 seventy-two第72 seventy-second第三组百hundred千thousand百万million十亿billion第四组¤英语中没有万、十万、千万、亿的单位。要表示的话需进行转换。万ten thousand十万one hundred thousand千万ten million亿a hundred million第五组表达几百，几千，几百万，几十亿时等确切的数字后面不加s，也不后接介词of表达成百上千，成千上万，数以百万计，数以亿计等不确切的数字后面要加s+of500 five hundred 成百上千 hundreds of3000 three thousand成千上万 thousands of400万 four million数以百万计 millions of50亿 five billion数以亿计 billions of¤a dozen 一打（12个）；two dozen 两打（24个）；dozens of 几打（几十个）¤常见错误：five hundreds, hundred of， two hundreds of第六组百位数个数基数词形式加“hundred”，表示几百，在几十几与百位间加上and.101one hundred and one386three hundred and eighty-six648six hundred and forty-eight999nine hundred and ninety-nine第七组 挑战更难的数字吧！英语读数字时，从数字的右端向左端数起，没三位数加一个逗号“，”。依次为从右到左依次为thousand, million, billion3,685three thousand six hundred and eighty-five2,727two thousand seven hundred and twenty-seven16,250,064sixteen million two hundred and fifty thousand 5,237,166,234five billion, two hundred and thirty-seven million, one hundred and sixty-six thousand, two hundred and thirty-four数词考点：1. 序数词前面要加定冠词the，表第几个。the first/second/thirdWhere do you live? I live on the second floor.2. 序数词可作形容词修饰名词，也可作副词修饰动词。即作副词时，first=firstly; second=secondly; last=lastly同学们观察一下，作形容词和作副词的序数词有什么不同？He wins the first prize.He arrives at the airport first(ly).Summary:序数词作形容词修饰名词时前要加定冠词the. 序数词作副词修饰动词时不要加定冠词the.3.当名词前面有序数词修饰或本身就是修饰词的时候，用不定式作后置定语。不定式作后置定语只能表主动哦！eg. the first/second/thirdto do sthHe was the first student to arrive in the classroom.难点：请同学们观察以下两个例句He was the first president to pass (pass) laws to stop slavery.John is the first foreign journalist interviewed (interview) by CCTV.¤注意：此题不能填to be interviewed. 因为序数词修饰名词时，不定式作后置定语，只能表主动。若表被动，则不用to do形式,用过去分词作后置定语表被动。4.作文分点陈述时可以使用序数词（以下两种形式拼写可通用）First/FirstlySecond/SecondlyThird/ThirdlyLast/Lastly5.表示人的不确切岁数或年代，用复数形式表示。in ones twenties 20几岁的时候 in ones fifties 50几岁的时候 in ones sixties 60几岁的时候eg. He became a professor in his thirties. 三十几岁的时候 It was in the 1960s. 那是在20世纪60年代¤表示确切的年龄时，用基数词+years old或at the age of+基数词eg. He looks quite healthy though he was seventy years old/at the age of seventy.6.时刻、日、月、年份表达和年代表达略有不同。eg. 7点钟 at seven oclock周三 on Sunday11月 in November3月15日 on March 15th 1991年 in 1991 20世纪80年代 in the 1980s 在古代 in the ancient times 在现代 in the modern times同学们观察出了有什么不同吗？小结：时刻、日、月、年份与年代表达时介词不一样。 时刻用at, 具体到某一天用on, 月份、年代用in。 时代一律用in。时刻、日、月、年份表达时零冠词。 时代表达时需加定冠词。6.英语分数 几分之几分数是用基数词和序数词一起表示的。基数词作分子，序数词作分母，当分子超过“1”时，其他情况下序数词都要用复数形式。1/3 one third2/3 two thirds4/5 four fifths¤特殊的表达形式：1/2 one half1/4 one quarter3/4 three quarters¤若分数作修饰语的时候，需加连字符。eg.Only one-fifth of air consists of oxygen. 氧气只占空气的1/5. Two-thirds of the students are non-Chinese.7.百分比的表达 基数词+percent（¤percent不变复数）16% sixteen percent88% eighty-eight percent97% ninety-seven percent8.基数词+名词构成复合形容词修饰名词，中间需加连字符，且没有复数形式eg.步行十分钟的路程 a ten-minute walk （注意minute后面不要加复数） 一条五十米宽的公路 a fifty-meter wide road 一个五岁的男孩 a five-year-old boy9.倍数表达法（1）倍数（分数）+as+adj+asThe earth is 49 times as large as the moon.（2）倍数（分数）+the size(amount,length,weight,width)ofThe earth is 49 times the size of the moon.（3）倍数（分数）+形容词（副词）比较级+thanThe grain output is 8 percent higher this year than that of last year.（1） increase/decrease by+倍数，表示增加/减少了多少倍The production of grain has increased by four times this year.这个房子是那个房子的三倍。This room is three times as large as that one.This room is twice larger than that one.This room is three times the size of that one.请同学们完成以下数词练习：语法填空练习：(1) _hundredth cave that George has discovered in his lifetime is near the Alps.(2) He looked quite healthy though he was _(70多岁的时候）.(3) _（几百万人）in the world are sending information by E-mail everyday.(4) _(成百上千的人）poured into the stadium to watch the basketball game yesterday.(5) It is not rare in _90s that people in their fifties are going to university for education.(6) He is always the first _(come) and the last _(leave)(7) Im honored to be the first foreign student _(invite) to deliver a speech here.改错练习：(8)She arrives the first.(9)Two-fifth of the land in that district is covered with trees and grass.(10)Forty percents of the students wear glasses.(11)It took us quite a long time to get there. It was a three-hours journey.(12)The room is three time as large as that one.学科网（北京）股份有限公司