外研版Book1Module5VocabularyandspeakingPPT.ppt

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1、英语中基数词、序数词、分英语中基数词、序数词、分数、小数和百分数的读法数、小数和百分数的读法1. 基数词的读法基数词的读法A. 先先“几十几十”， 再再“几几”，中间用连字，中间用连字符。符。e.g. 23 89B. 先先“几百几百”， 再加再加and, ,再加末两位。再加末两位。e.g. 223 416 809 twenty-three eighty-ninetwo hundred and twenty-threefour hundred and sixteeneight hundred and nineC. 1000以上的数从后向前数，每三位数以上的数从后向前数，每三位数 加加“,”；第一

2、个；第一个“,”号前为号前为thousand; 第第 二个二个“,”号前为号前为million; 第三个第三个“,”号号前前 为为billion。e.g. 1,001 9,743 750,000,000 one thousand and onenine thousand, seven hundred and forty-threeseven hundred and fiftymillion2. 序数词的读法序数词的读法序数词一般以与之相应的基数词加序数词一般以与之相应的基数词加-th构构成，如：成，如：tenth（第十），但下面这些基（第十），但下面这些基数词在变序数词时，数词在变序数词时，

3、有特别的地方。有特别的地方。A. one two three five eight nine twelvefirstsecondthirdfiftheighthninthtwelfthB. 以以-ty结尾的词，先变结尾的词，先变-y为为-i，再加，再加-eth。e.g. twenty fortyC. 以以one, two, three, five, nine收尾的多位收尾的多位 数词，要照第一条方法变。数词，要照第一条方法变。e.g. twenty-one twenty-two ninety-nine a hundred and fifty-three twentiethfortiethtwe

4、nty-firsttwenty-secondninety-ninth a hundredand fifty-third基数词表示分子，序数词表示分母，基数词表示分子，序数词表示分母，分子大于分子大于1时，序数词要用复数。时，序数词要用复数。e.g. 1 / 4 2 / 3 7 / 9 5 / 12 one-fourthtwo-thirdsseven-ninthsfive-twelfths3. 分数词的读法分数词的读法特殊的表达法特殊的表达法 a / one halfa / one quarterthree quarters4. 小数的读法小数的读法7.8 0.125 14.397 seven

5、point eightzero point one two fivefourteen point three nine seven5. 百分数的读法百分数的读法27% 45% 86% twenty-seven percent forty-five percent eighty-six percentCan you say the following in English correctly?1,000 2,000 12,000 112,000796,000one thousandtwo thousandtwelve thousandone hundred, twelve thousandsev

6、en hundred, ninety-six thousand879,457eight hundred, seventy-nine thousand, four hundred and fifty-seven 1,000,000 9,000,00032,000,000 212,000,000one million nine millionthirty-two milliontwo hundred, twelve millionRead these questions aloud and say the answers.1. What is 1 / 2 of 6,000,000?2. How m

7、uch is 35,246,000 plus 12,800,000?3. What is 25% of 200,000,000?three millionforty-eight million, forty-six thousand fifty million4. How much is 260,408,396 and 5,284,700? two hundred, sixty-five million, six hundred, ninety-three thousand, ninety-six 5. What is of 1,000,500,000? seven hundred, fift

8、y million, three hundred, seventy-five thousand 6. What is 10% of 800,000,000? eighty million 1/5 1/61/74/7one fifthone sixthone seventhfour seventhsCan you say the following in English correctly?7/10 97/111seven tenths ninety-seven one hundred and elevenths forty-five eighty-sevenths总结总结: 你能看出他们有什么

9、特点吗？你能看出他们有什么特点吗？45/87分子用基数词分子用基数词, ,分母用序数词分母用序数词;分子大分子大于于1,分母的序数词需要加分母的序数词需要加s。另外另外, 还有几个特殊表达的情况还有几个特殊表达的情况:1/21/4 1/3 3/42/3one half one quarter one third three quarters two thirds Now say these fractions. 2/5 5/8 9/10 3/8 5/6two-fifths five-eighthsnine-tenthsthree-eighths five-sixthsCan you say t

10、he following in English correctly?0.50.80.761.23point fivepoint eight point seven sixone point two three23.45100.3287.6757.564twenty-three point four fiveone hundred point three two eighty-seven point six seven seven point five six four 1. Finish Exercise 9 on P93.2. Work in pairs. Give your partner five sums. Use numbers over a million.