基数词序数词重点难点解析讲解与练习 数词是用来表示事物和数量的顺序的词，分为基数词和序数词两种。 基数词 功能 做主语、宾语、表语、定语、同位语 读法三要点 A．记31个词：基数词1~19，20~29整十位数和hundred, thousand, million, billion B．会读个、十、百位数 C．由右向左每三位数前的逗号分别读做thousand, million和billion,逗号之间的按百位以内的数读 注意 A．表示“几百”、“几千”时，hundred, thousand等词不加s B．hundred, thousand等词为复数时做名词，表示“数量很多”的意思 序数词 构成 A．一般的基数词后+th，多位数的基数词只变最后一位。如：ten→tenth B．整几十的基数词，去掉词尾的y再加ieth，如：thirty→thirtieth C．几个不规则词：first, second, third, fifth, eighth, ninth, twelfth  功能 做定语，前面加the；年、月、日中的日；表示“第几”时；分数中的分母 语法易错题 英语单词快速记忆 初中英语试题 一 基数词：表示数目的词为基数词，它的构成如下表： 范  围 特  点 实    例 1~12 无规律 one, two, www.ks5u.comthree, four, five, six, seven, eight, nine, ten, eleven, twelve 13~19 以teen为结尾 thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen 20~90 以ty结尾 twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety 21~99 十位与个位之间要加连字符 “-” twenty-five, sixty-five, ninety-nine 101~999 百位与十位之间通常用and three hundred and twenty-five（美语中常将and省略） 千以上 6275—six thousand two hundred and seventy-five；1200—twelve hundred 二 序数词：表示顺序的数词为序数词，它的构成如下表： 范  围 特  点 实    例 1~19 各基数词尾加th 其中七个例外：first, second, third, fifth, eighth, ninth, twelfth, 其余，如：four — forth, six — sixth, nineteen — nineteenth 20,30~90 把y变i后加eth twentieth, fortieth, ninetieth 21以后多位数 最后一个数用序数词，其余用基数词 21st — twenty-first, 110th — one hundred and tenth 根据句意将括号内的汉语译成英语 1.It is not rare ________________（在九十年代） that people in their fifties are going to university for further education.  2.______________ （三分之二）of the land in that district is covered with trees and grass.   3. Americans eat __________________ （两倍多的）as many vegetables per person today as they did in 1910.    4.The earth is ______________ (49倍)the size of the moon.  5.The grain output of this year is ___________________ （高8%）than that of last year. 6._______________ ¬¬¬（几百万）people in the world are sending information by E-mail every day.   7．The hero of the story is an artist ____________________ （三十多岁）．   8．Mr Smith asked me to buy _____________（两打）eggs for the dinner． 9．—Tell me where you live，please． —I live____________________（在和平路123号）．             10. About ______________________ ( 三千人)took part in the demonstration against the war on Iraq. 11. The rice production has __________________________ (增加了 5.8%) this year.  12. There were fifteen presidents before Abraham Lincoln, so he was _____________ ( 第十六任)president. 13. It will take me ____________________________( 一年半的时间) to finish the course. 14. Is the Yellow River ___________________________(第二大河 )in China? 15. ______________________ (开始的三个部分 )of the text are rather difficult for us beginners. 16. I will stay here for _________________(一两天 ). 17. He lived in _________________________________(五楼506房 ). 18. The class was over. The students went out of the classroom __________________( 三三两两地).   答案：1. in the 90s  2. Two fifths  3. more than twice  4. 49 times  5. 8 percent higher 6.Several million 7．in his thirties 8.several dozen 9．at 123 Heping Street 10. three thousand people 11. increased by five point eight percent 12. the sixteenth 13. one and a half years’ time 14. the second largest 15. The first three parts 16. one or two days 17. Room 506 on the fifth floor 18. in twos  or threes