1、2017中考英语语法精讲:数词【教学目标】1.掌握基数词和序数词的用法2.学会分数和百分数的表达3.会表达年份【教学内容】数词分为基数词和序数词两种。表示数目或数量多少的词叫基数词;表示数目顺序的词叫序数词。一、基数词1112的基数词是独立的单词,即: one,two,three,four,five,six,seven,eight, nine,ten,eleven,twelve。21319的基数词以-teen结尾。如:fourteen,seventeen等但13,15,18较特殊, 13thirteen 15fifteen 18eighteen。32090的整十位均以-ty结尾。如:sixty
2、,ninety但20,30,40,50,80较特殊, 20twenty 30thirty 40forty 50fifty 80eighty。4十位数与个位数之间要加连字符号“-”,如:28twenty-eight,96ninety-six。5百位和十位(若无十位则和个位)之间加and,如:148one hundred and forty-eight 406four hundred and six。6hundred(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:600six hundred,8百万eight mil
3、lion。71000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:2,510two thousand five hundred and ten;84,296eight-four thousand two hundred and ninety-six;274,350two hundred and seventy-four thousand three hundr
4、ed and fifty。8hundred,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 ofmillions of 复数名词,其前面不能加具体的数词,但可加several或 many。9基数词单数名词形容词构成合成形容词。如:一个五岁的男孩a five-year-old boy;一座800米长的桥an 800-metre-long bridge;女子400米接力girls 400-metre re
5、lay race。10. 基数词的特殊用法:(1)表示“几十年代”或“几十岁”时,用逢十的基数词的复数形式。如:in the 1990s 20世纪90年代in ones twenties在某人20多岁时(2)用在习语中。如:in twos and threes三三两两地二、序数词1.基数词变序数词可利用口诀巧记:1,2,3特殊记,加th 从4起 (first, second, third, fourth)8少t,9去e,千万别忘记 (eighth ,ninth)逢5逢12,ve变f (fifth ,twelfth)20到90,y要变ie (twentieth ,ninetieth)若是几十几,
6、前基后序别倒位 (ninety-first, nine-hundredth)序数词应注意的几点事项:1. 当序数词用阿拉伯数字表示时,必须在数字后加上序数词的最后两个字母。如:21st第2132nd第322. 序数词前一般要用定冠词the如:Sunday is the first day of a week.星期天是一周的第一天。三、分数和百分数1. 分数(1)分数的分子用基数词,分母用序数词。如:one fifth五分之一one tenth十分之一(2)当分子大于1时,分母用序数词的复数。如:two thirds三分之二five eighths八分之五(3)当分子是1时,可以用one也可以用
7、a.如:a second = one seconda third = one third(4)当分母是2和4时,分别可以用half和quarter代替。如:a half二分之一three quarters四分之三2. 百分数百分数用percent表示。如:forty percent百分之四十three percent百分之三3. 分数、百分数与主谓一致分数、百分数的考查往往和主谓一致相联系。当分数、百分数修饰可数名词的复数时,谓语动词用复数形式;当分数、百分数修饰不可数名词时,谓语动词用单数形式。如:Eighty percent of the students in our school co
8、me from Hainan.我们学校百分之八十的学生来自海南。Three fourths of the students in my class are interested in English.我们班四分之三的学生对英语感兴趣。Two thirds of the water on the earth is sea water.地球上三分之二的水是海水。四、数词的应用1钟点的表示:小时、点钟、分钟、秒钟要用基数词。“几点钟”用基数词加oclock。oclock可省略。如:现在是5点钟。Its five(oclock)“几点过几分,30分钟”用介词past。如:7:05five past s
9、even;7:15fifteen(a quarter)past seven;7:30half past seven。“差几分几点”用介词“to”。注意:整点加“1”且用 60减去目前的分钟数。如:7:40twenty to eight;7:45fifteen(a quarter)to eight。日常生活中的时间读法常常简化,直接按基数词的顺序读。如:7:05seven o five;7:15 seven fifteen。2编号的表示:Lesson One the first lesson第一课;Bus No3the No3bus. 3路公共汽车;表示住所时不用“No”如:302房间Room
10、302(读作:room three o two);如果编号的数词比较长,一般用基数词。如:Page 457第457页;电话号码,用基数词,可单个读,重复的数字也可读“double”,如:3855633three eight five five(double five) six three three(double three)。3年月日的表示:年份用基数词,先读前一位或两位,再读后两位。如:1999nine- teen ninety-nine;1900nineteen hundred;2000two thousand;1905nineteen o five;年用基数词,日用序数词。如:1998
11、年6月8日写作:June 8,1998;读作:June the eighth, nineteen ninety-eight或the eighth of June, nineteen ninety-eight。4.倍数的表示法:表示“几倍大小(长短;数量)”,由“倍数+ the size(length,amount)”结构组成。如:The earth is several times the size of the moon.地球是月球的几倍大。表示“比大几倍”,由“倍数+形容词(副词)比较级+ than +被比较部分”结构组成。如:This box is three times bigger
12、than that one.这个盒子比那个盒子大三倍。表示“是倍”,由“倍数+ as +形容词+ as +被比较部分”结构组成。如:Our factory is twice as big as theirs.我们的工厂是他们的两倍大。五、特殊用法1数词作主语,谓语动词用单数。如:Two months is quite a long time两个月是相当长的一段时间。Four and two is six四与二的和是六。Whats two and three?二与三的和是多少?2一个半小时(一年半,一个半月可类推)one/an hour and a half one and a half hours。3不定冠词a/an用在序数词前表又一、再一。如:Though he had failed twice,he wanted to try a third time.尽管他已失败了两次,他还想再试一次。The little monkey has had three apples,and he wants to eat a fourth one.那只小猴子已经吃了3个苹果,他还想再吃一个【课内检测】详见导学案【作业布置】1.完成本节课的同步练习2.预习下一讲的导学案。