人教版高中英语选修英语语法与词汇NUMBERSANDQUANTITIES课件.ppt

1、NUMBERS AND QUANTITIESRead and Answer1.HIV infections are increasing at a meaningful rate among migrant workers in Mexican.()2.What was the rate of HIV infections among women giving birth at Tijuana General Hospital?TThe rate was four times higher than that in the general population of either countr

2、y.3.As much as 2000 people are infected with HIV，according to the results of a study of 600 migrant workers in Californias Fresno and San Diego counties.()F数词1.定义：表示数量或顺序的词叫做数词。2.分类：表示人或事物数量多少的数词叫基数词，如one，two，three，ten等；表示人或食物顺序的数词叫序数词，如first，second，fourth等。A.A.基数词基数词1.1.构成：构成：(1)112记成：one，two，three

3、twelve。(2)1319词尾为teen，thirteen，fourteen，fifteen(3)20，30，40逢10词尾为ty，twenty，thirty(4)2199十位数字和个位数字之间加连词符，twenty-one(5)101999先说几百，再加and，再加末尾两位数(末位数)eg：178 one hundred and seventy-eight.(6)大数的表达：hundred，thousand，million等词在表示具体数量的时候用单数；表示“成上”要用复数，例如；thousands of成千上万的2.2.位置：位置：(1)位于another，all之后，如：Can I h

4、ave another two cakes？(2)可置于last，next，other之前或之后，如：His last two books are written in English.=His two last books are written in English.他的后两本书是用英语写的。B.B.序数词序数词1.常见的序数词：first-1st；second-2nd；third-3rd；thirty-first-31st。2.序数词的构成方法口诀:一，二，三要全变；(one-first;two-second;three-third)其余都加th,th里有例外，8去t,(eight-ei

5、ghth)9去 e(nine-ninth)字母f代ve(five-fifth;twelve-twelfth);ty变成 tie(twenty-twentieth)若要变化几十几，只变个位就可以(twenty-one twenty-first)3.用法：(1)一般情况下，序数词前面要加定冠词the例：I have already got two letters from Susan this year,so this is the third one.(2)序数词前加定冠词和冠词的区别：例：Ill go to Beijing a third time next month.（已 经去过两次了。I

6、 have a fourth apple.（我已经吃了三个，又 吃了一个，a fourth one.）The third time I went to Beijing was in 1998.C.C.英语中小数、百分数和分数的表达英语中小数、百分数和分数的表达1.分数：分数的构成总则为：分子用基数词，分母用 序数词，中间用连词符连接。分子为1的分数，分子用基数词，分母用序数词，如：1/3 one-third 1/3 one-fourth分子大于1的分数，分母的序数词要加s，如：2/3 two-thirds 3/5 three-fifths带分数的表示：基数词+and+分子基数词+分组序数词，如

7、：2又3/5 two and three-fifths 1又1/2 one and a half分子与分母都较大的时候，用over来表示，如：22/9 twenty-two over nine2.2.百分数百分数u 百分数的表示法为：基数词+%，百分号读作percent。89%-eighty-nine percent 100%-one hundred percent3.3.小数小数u 小数的表示法和汉语中的小数表示法一样，小数点后 面的数字是“见几读几”，点用point来表示。0.125-zero（或者o）point one two five 27.832-twenty-seven point

8、 eight three twoD.D.英语中动物的英语中动物的“群体群体”有多样化的表达，不同有多样化的表达，不同 的词语表达不同的动物。的词语表达不同的动物。a colony of：群居在一起的动物。如：a colony of ants a flock of：一起吃食或行走的兽群，尤指羊群。如：a flock of sheep a herd of：一起吃食或行走的兽群，尤指牛群。如：a herd of cattle a school of：共游的鱼群。如：a school of fish an army of：大队，大群。如：an army of workmen.E.E.表示容量或形状的短

9、语可以表达不可数表示容量或形状的短语可以表达不可数 名词的量。名词的量。a bag of：一袋。如：a bag of toffees.a jar of：一罐。如：a jar of jama roll of：一卷。如：a roll of papera loaf of：一条。如：a loaf of breada strip of：狭长的一条。如：a strip of landF.F.表示不定数量的常用词组。表示不定数量的常用词组。用于可数名词用于可数名词用于不可数名词用于不可数名词可数名词和不可数可数名词和不可数名词均可用名词均可用a bit of(a)few fewer(a)little all

10、(the)fewest lessa lot of；lots ofseveral；manydealenougha(great)number ofa great ofplenty ofdozens of(the)leastsome；anymuchG.G.表示长、宽、高、重量、体积时，需要表示长、宽、高、重量、体积时，需要 用特定词组或特定结构。用特定词组或特定结构。in size：在大小，尺寸方面。如：It is equal in size to a turkey.in length：在长度上。如：What is that,ten centimeters in length?in depth：在深

11、度上。如：Contradictions grow in breadth and in depth.in area：在面积上。如：Although large in area,the flat did not have many rooms.in width：在宽度方面。如：The ship is sixty feet in width.H.H.约数表达法约数表达法1.“大约”用about，nearly，around来表示。如：The pig weighs about 80 pounds.2.“多于，超过”用over，more than来表示。如：The bridge is over 150 m

12、eters long.3.“少于，不超过”用less than来表示。如：She is less than twenty years old.4.“左右”用or so来表示。如：In the past fifty years or so,scientists have been able to“see”farther and farther into the sky.Lets check1.I wonder of I ask him()time.A.four B.fourth C.the fourth D.a fourth解析：序数词前面加不定冠词表示“又一次”。2.He came out()in the track events.A.first B.one C.the first D.the one解析：这里first可以看成表语，也可以看作一种“取得第一名”的习惯看法。3.He was only in()at the time.A.in his 20s B.the 20s C.his twenties D.the twentiesCDA 熟记本课时的重要单词与句型并各默写五遍。