1、专题三 数词1.基数词（1）基数词的构成表示数目的数词为基数词，其构成如下：考考 点点 1 基数词与序数词【歌诀助记】基数词不难记，找出规律很容易。零至十二样各异，一个一个单独记。后加teen变十几，thirteen，fifteen看仔细。十八需要看仔细，eighteen只有一个t。二十到九十加ty，twenty，eighty重点记。forty去掉字母u，thirty，fifty更出奇。十位数后接个位，表示数字几十几。排列顺序不费力，连字符号莫丢弃。写到几百几十几，and把百与十系。（2）基数词的用法表示数量的多少。例句 There are twenty-five desks and chai
2、rs in our class.我们班里有25张桌椅。表示年份和年龄。例句 He was born in 1952.他出生于1952年。She is fifteen years old.她15岁。表示时刻。表示顺序或编号。其结构为“单数名词基数词”，名词的第一个字母通常要大写。如Class Two，Room 12，No.3 Middle School，Page 10。another+基数词（大于1）+复数名词=基数词（大于1）+more+复数名词，表示“又几个、另几个”。例句 We need another two bananas to make the milk shake.=We need
3、 two more bananas to make the milk shake.制作这个奶昔我们还需要两根香蕉。特别提示“基数词+连字符+单数名词(+连字符+形容词)”可构成复合形容词，作定语。例句 I have an eight-year-old brother.我有一个8岁大的弟弟。We will have a two-week holiday next month.下个月我们将有一个两周的假期。“基数词度量单位形容词(long/wide/deep/high)”表示计量。例句 My uncle is 1.92 meters tall.我叔叔身高1.92米。【特别提示】“单数名词基数词”可
4、转换成“the序数词单数名词”，此时名词的首字母不大写。如：Lesson Threethe third lesson第三课。2.序数词（1）序数词的构成表示顺序的数词为序数词，其构成如下：【歌诀助记】基变序，有规律，一、二、三特殊记，first,second,third；从四开始加-th,八去t，九去e；五和十二变ve为f，再加-th；整十变y为ie，再加-th；若想表示几十几，只变个位就可以。（2）序数词的用法表示顺序。序数词表顺序时，其前须用定冠词the，后接单数名词。例句 Im the first one to arrive here.我是第一个到达这里的。用于最高级前。例句 John
5、is the second tallest boy in our class.约翰是我们班上第二高的男孩。用于构成分数。构成分数时，分子用基数词，分母用序数词。分子为1，分母用单数；分子大于1，分母用复数。例句 one fifth五分之一;three fifths五分之三。与不定冠词a/an连用时，表示“又一；再一”。例句 I have been to Beijing twice,but I would like to go there a third time.我已经去过北京两次了，但是我想再去一次那里。【特别提示】若序数词前出现形容词性物主代词，则不加the。定语从句中先行词之前有序数词时
6、，则关系代词只能用that。例句 Today is my thirtieth birthday.今天是我的三十岁生日。例句 Mary was the first student that finished the homework.玛丽是第一个完成作业的学生。“分数+of+名词”作主语时，谓语动词的数取决于of后面的名词。其后的名词是可数名词复数，谓语动词用复数；其后的名词是不可数名词，谓语动词用单数。例句 Two thirds of the students are boys in our class.我们班三分之二的学生是男生。Three fifths of her money is sp
7、ent on books.她把五分之三的钱花在了买书上。【导图助学】用方框中所给词的适当形式填空用方框中所给词的适当形式填空two,twentieth,three,ten,eighty1.It was my grandmas _ birthday yesterday.We had a big family dinner.2.Mothers Day is on the _ Sunday of May.3.Susan usually gets to school early.This morning,Susan was the _ to come to school among all the s
8、tudents.4.My house is near the school.It only takes me _ minutes to walk to school every day.5.There are twelve boys and eight girls in the classroom,which means _students in total.eightiethsecondthirdtentwenty.完成句子完成句子:1.这是我第一次游览西安。这是我第一次游览西安。This is _ for me to visit Xian.2.请将书架上左边第七本字典递给我。请将书架上左边
9、第七本字典递给我。Please pass me the _ dictionary from the left on the bookshelf.3.他出生于他出生于20世纪世纪90年代。年代。He was born_.the first timeseventhin the 1990s考考 点点 2 概数词 表示大致数目的词叫概数词，常使用ten，twenty，hundred，thousand等基数词的复数形式来表达。其用法主要有：1.表示大致年龄，常用“in ones+整十的基数词复数”结构。例句 In his sixties，he rode a bike round the world.在他
10、六十多岁时，他骑自行车环游世界。The old woman is in her nineties.这个老太太九十多岁了。2.表示世纪年代，常用“inthe基数词复数/基数词s”结构。例句 The light was invented in the 1870s.电灯在十九世纪七十年代被发明。3.“计数单位的复数+of+复数名词”结构表示概数。ten,hundred,thousand,million,billion等词可以采用此结构，表示不确切的数量。此时，这些词之前没有具体数目，其后遵循两个“有”原则：即有“s”和“of”。【特别提示】“二十多岁”要说成twenties，指“20岁到29岁”。依
11、此类推，thirties表示“三十几岁”，forties表示“四十几岁”，但“十几岁”不可说tens，而要说teens，指“13岁至19岁”。例句 He died in his thirties.他三十多岁去世的。She is in her teens.她十几岁。“具体数字计数单位名词复数”结构表示确切的数字。此时，hundred,thousand,million等词与具体的数字或several,some,many等连用时，必须用单数形式。如：five hundred students 500名学生；two thousand books 2 000本书；many million trees 几
12、百万棵树。【特别提示】例句 There are six hundred workers in this factory.这家工厂有600名工人。“计数单位的复数of名词复数”结构意为“数以计”，表示概数。此时，hundred,thousand,million等词必须使用复数形式，不能被具体数字修饰，且其后与of连用。例句 Thousands of visitors have come to Hangzhou during the last two weeks.在过去的两周，成千上万的游客来到杭州。()1.Basketball is so excited that people play it
13、for fun.A.Million B.million of C.millions of D.millions()2.To his surprise,he was chosen from three students to give a speech in front of teachers,parents and other students.A.thousands of B.thousands C.thousand of D.thousand()3.The environment here becomes better and better.birds are coming back.A.Thousands of B.Thousand of C.Thousands D.ThousandCDA完成句子完成句子:1.数百万农民离开他们的家乡到城市里工作。数百万农民离开他们的家乡到城市里工作。_ farmers leave their hometown to work in the cities.2.这所学校里一共有这所学校里一共有2000个学生。个学生。There are _ students in total in this school.Millions oftwo thousand
