数词用法知多少.doc

数词用法知多少近几年的中考中，经常有涉及数词方面的知识,也是学生经常出错的地方。本文就数词的用法作一归纳,供大家在复习中参考。一、 除了从1-12个基本数词（基数词）用不同的词表达外，从13-19后都有-teen后缀。如：one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen， fourteen， fifteen，sixteen， seventeen， eighteen， nineteen二、 从20至90之间表整十的数词都跟后缀-ty。如： twenty， thirty， forty， fifty， sixty， eighty， ninety 表示“几使几”用整十加个位数构成，中间用连字符“-”。如： twenty-one， thirty-two， forty-three， fifty-four， ninety-six三、 表示几百，几千，几百万，十亿用数词1-9加hundred，thousand， million，billion构成。如： four hundred， five thousand， seven million， nine billion 注意：几百几十之间一般用and连接。如： three hundred and forty- nine， six hundred and seven四、 表示不确定的“数百”，“数百万”，“数千”，“数十亿”时，用“hundreds”，“thousands”，“millions”，“billions”加“of”构成。如： There are hundreds of teachers in our school. Thousands of students are studying in our school. The mountain is covered with billions of trees.五、 表示顺序的词（序数词）除1-3外，其余的后面都有后缀-th。如： first， second， third，fourth， fifth， ninth， eleventh， twelfth六、 整十的序数词后面是由基数词变y为i，再加eth构成。如： twenty twentieth， eightyeightieth， ninetyninetieth 其余的整数加个位数构成的词，只变个位数为序数词即可。如： twenty-ninetwenty-ninth，forty-fiveforty-fifth，fifty-sixfifty-sixth，sixty-sevensixty-seventh，ninety-seven ninety-seventh七、 序数词前一般加定冠词the，但有时加不定冠词表示“又一”，“再一”等。如：I have tried twice. I want to try a third time.He has failed three times. He will try a fourth time.八、 数词与名词连用时，如几号，几班，几年级，房间号及邮编号码时，首字母都大写。如： Number One， Class Three， Grade Two， Room 218， Zip Code 257091九、 表示倍数的大小时，两倍用twice表达，三倍以上用数词加times表达。如： My school is twice as large as theirs. Five times seven is 35.十、分数的表达：分子基数词，分母序数词，分子大于1，分母加s。如： 1/4 one fourth，3/4 three fourths（three quarters）， 1/5 one fifth， 4/5 four fifths十一、小数的表达，小数点读作point，其余的按基数词读出。如：0.2 zero point two， 5.79 five point seven nine十二、百分数的表达，百分号读作percent。如： 10% ten percent， 16% sixteen percent， 0.7% point seven percent, 89%eighty-nine percent十三、数词算式表达：+plus，minus，×multiplied ÷divided。如： 5+7five plus seven， 93nine minus three， 8×9eight multiplied by nine， 64÷8sixty divided by eight， 6：5 the ratio of six to five， 42 four squared， 33three-cubed， 54the fourth power of five十四、与数有关的几个常用单词及词组。如： half 一半， a dozen 一打， dozens of 几十， a score 二十， scores of 许多， several（a few），几个，数个巩固训练1. About _ of the workers are young man.A. third fifths B. three fifths C. three fives D three fifth2. The computer of this kind can work _ than that kind.A. hundreds of times faster B. hundred of times fasterC. hundred times faster D. a hundred time faster2. Two _ died of flu last year.A. hundred old people B. hundreds of old peopleC. hundreds of people D. hundreds old people3. He graduated in _ of _ centrury.A. the sixtieth; twenty B. sixty; the twentiethC. the sixties; the twentieth D. sixty; twenty4. The two great men wrote those letters in _.A. 1870s B. 1870s C. the 1870s D. the 18705. I wonder if I can ask him _ time.A. four B. fourth C. the fourth D. a fourth答案: 1-5 B A A C D4