Module-5-A-Lesson-in-a-Lab-Introduction课件.ppt

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1、 Look at the pictures collected by our classmates. Do you know the name of these equipment？test tube tongs balancecrucible beaker & glass rod Bunsen burner Since you are interested in doing scientific experiments, now lets get to know some vocabulary and knowledge related to science and experiment.P

2、otassium （钾）（钾） Sodium(钠钠) Calcium(钙钙) Magnesium(镁镁)Aluminium（铝）（铝） Zinc （锌）（锌） Iron （铁）（铁） Copper （铜）（铜）英语中基数词、序数词、分数、小数和百分数的读法1.基数词的读法：基数词的读法：A. 先说先说“几十几十”， 再说再说“几几”，中间，中间用连字符。如：用连字符。如：23 89B. 先说先说“几百几百”， 再加再加and, ,再加末两位再加末两位数（或末位数）。如：数（或末位数）。如：223 416 809 twenty-three eighty-ninetwo hundred and t

3、wenty-threefour hundred and sixteeneight hundred and nineC. 1000以上的数先从后向前数，每三位数加以上的数先从后向前数，每三位数加一一“,”（千分位）；第一个（千分位）；第一个“,”号前为号前为thousand; 第二个第二个“,”号前为号前为million; 第三个第三个“,”号前为号前为billion。如：。如：1,001 4,000 9,743 174,301750,000,000 one thousand and onefour thousandnine thousand, seven hundred and forty-t

4、hreea (one) hundred and seventy-four thousand, three hundred and oneseven hundred and fifty million2.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词序数词一般以与之相应的基数词加词尾尾-th构成，如：构成，如：tenth（第十），但下（第十），但下面这些基数词在变序数词时，面这些基数词在变序数词时， 有特别有特别的地方。如：的地方。如：A. one two three five eight nine twelvefirstsecondthirdfiftheighthninthtwelf

5、thfractionWe write1/5 1/61/74/7We sayone fifthone sixthone seventhfour sevenths7/10 97/111seven tenths ninety-seven one hundred and elevenths 45/87forty-five eighty-sevenths总结总结: 你能看出他们有什么特点吗？你能看出他们有什么特点吗？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

6、/3 3/42/3A half is the same as 50 percent.one half one quarter one third 33.33r % r:recurringthree quarters two thirds 66.66%50%25%75% 百分数：百分数： percentage5) 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

7、,000 112,000796,000one thousandtwo thousandtwelve thousandone hundred and twelve thousandseven hundred and ninety six thousand879,457eight hundred and 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 an

8、d twelve million988,766,688nine hundred and eighty-eight million, seven hundred and sixty-six thousand, six hundred and eighty-eight987,654,321nine hundred and eighty-seven million, six hundred and fifty-four thousand, three hundred and twenty-one1,000,000,000one billion9,000,000,000nine billion32,0

9、00,000,000thirty-two billion564,865,000,000five hundred, sixty-four billion, eight hundred, sixty-five million978,876,675,467nine hundred and seventy-eight billion, eight hundred and seventy-six million, six hundred and seventy-five thousand, four hundred and sixty-seven PracticeNow lets say: 2/5 5/

10、8 9/10 3/8 5/6two-fifthsfive-eighthsnine-tenths three-eighthsfive-sixthsCan you say the 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 five

11、 seven point five six four pointpointpointpoint总结：小数点用pointRead these questions aloud and say the answers. What is of 6,000,000?2. How much 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, fifty million, three hundred, seventy-five thousand 6. What is 10% of 800,000,000? eighty million HomeworkFinish Exercise 9 on P 93.