1、Chapter 4,Grade Seven shawan Middle School初一年级组,A What do you know about?,1 a decimal numbers 2 a pair of odd numbers 3 a fraction 4 zero 5 add;plus 6 subtract;minus 7 mutiply; times 8 divide 9 a number showing degrees 10 a percentage 11 a pair of even numbers 12 equals,A + B 0 C 5/8 D E = F 13 45 G
2、 8 210 H 90 I J 0.82 K 45% L ,Numbers, Everyones Language,24561935891521=?,Calculating Machine,an abacus,Calculating Machine,one of the first calculating machines accurate and fast represent,beads,wires,5,7 2 4, thousands, hundreds, tens, ones,an abacus,Calculating Machine,an electronic calculator,a
3、dd,subtract,multiply,divide,percentage,square root,calculate,Calculating Machine,an electronic calculator,A: What can an electronic calculator do? B: It can _, _, _ and _. A: What else can it do? B: It can calculate _ and _.,add,subtract,multiply,divide,percentages,square roots,Calculating Machine,a
4、n electronic calculator,A: What can _ do? B: It _. A: What else can it do? B: It _.,Calculating Machine,powerful a flash in your whole lifetime,a computer,Calculating Machine,A _ is a very _ calculating machine. In _, it can do a calculation that you could not do _ _.,a computer,computer powerful a
5、flash in your whole lifetime,powerful a flash in your whole lifetime,Read the text,Competition,Answer the questions,Why do people still use abacuses today?,Because they are accurate and fast.,What can an electronic calculator do?,It can add, subtract, multiply and divide. It can also calculate perce
6、ntages and square roots.,How fast can Shakuntala Devi calculate?,She can calculate like lightning.,How long can a computer do a calculation?,In a flash.,How long did the computer take to solve the difficult problem?,A minute.,What should people do to make computers calculate?,People have to_ _.,prog
7、ram them with instructions,What do the beads on the wires represent?,They represent _ _,ones, tens, hundreds, thousands and so on.,How many languages do you know? Everyone knows at least two his or her own language and the international language of numbers.,Numbers: everyones language,（他或她自己 的语言）,An
8、cient numbersIn ancient times, people wrote numbers in many different ways. However, they nearly all counted in tens.,different ways of writing the number 6,（在古代）,（以很多 不同的方式）,（以十为单位）,ZeroThe system of numbers today consists of the numbers from 1 to 9 and 0(zero). The Indians first invented and devel
9、oped the 1 to 9 system of numbers. They then invented the zero. The invention of the zero helped people write big numbers and calculate more easily. Now use each of these ten numbers once to write the biggest number. What is it?,（数字体系）,（invent. v.invention n.inventor n.）,1 ancient: many many years a
10、go (a) 2 consists of: includes (b) 3 invented: made for the first time (b) 4 accurate: without mistakes (a) 5 percentages: amounts out of a hundred (a),C1 Find these words in the article on page 45. Read the words around them and choose the best meanings.,A B 1 international a grew bigger or stronge
11、r 2 system b a group of things working together 3 developed c count with numbers 4 calculate d strong 5 bottom e used by more than one country or nation 6 powerful f in the lowest place,C2 Find the words in Column A in the article and match them with the meanings in Column B.,1 A calculating machine
12、 using wires and heads.An _ 2 A small machine using electronic power to do calculations.A _ 3 A very powerful machine for doing calculations.A_,C3 What do the following descriptions refer to? Write down the correct names in the blanks.,calculator,computer,abacus,D Find the facts,May asks T M Li, the
13、 writer, some questions about his article on numbers. His answers are not always clear. Read the article and make Lis answers clearer. Write one word in each blank.,1 Every one knows it.Knows what?The Language of numbers.,2 Long ago, people wrote them in many different ways.Wrote what?Numbers. 3. Pe
14、ople all count in this way.In what way?In tens. 4. The Indians invented that system of numbers.Which system of numbers?The 1 to 9 system.,5 The invention helped people write in big numbers.What invention?The invention of the zero.6 They are fast and accurate.What?Abacuses.7 Computers are very powerf
15、ul ones.Very powerful what?Calculating machines.,Language points,1. at least 至少= not less than,We should recite at least 10 English words every day.,反义词: at most 至多,The concert hall can hold at most 1,000 people.,2. in ancient times 在古代,= long long ago,= once upon a time,In ancient times, people use
16、d stones as money.,ancient 反义词: modern 现代的,times = age n. 时代,3. consist of 由组成,= include = be made up of,Our class consists of 25 girls and 30 boys.,4. invent = make sth. for the first timev. 发明; 创造,The ancient Chinese invented the compass.,invention n. 发明 inventor 发明家,5.develop = grow better or big
17、ger v. 发展; 发育 development n. 发展,The Indians first invented and developed the 1 to 9 system of numbers.,developing adj. 发展中的 developed adj. 发达的,India is a developing country. The USA is a developed country.,6. help sb (to ) do sth. = help sb. with sth.,I like helping my mother do the housework.,= I l
18、ike helping my mother with the housework.,7. stand for = represent 代表; 表示,PRC stands for Peoples Republic of China.,8. in a flash = very quickly = in a very short time 一瞬间;很快,A computer can do a calculation in a flash. 电脑可以在一瞬间完成计算.,9. Why not do sth.?= Why dont you do sth.?,Why not see a film tonig
19、ht?,= Why dont you see a film tonight?,10.buy sb.sth.= buy sth. for sb.,My mother bought me a new bike last month.,=My mother bought a new bike for me last month.,Grammar,I .Imperative sentences 祈使句,1 祈使句:表示请求,命令,劝告,祝愿或建议的句子.e.g. Close the window, please.e.g. Be quiet.2 使用祈使句应注意的几点. A: 肯定祈使句的谓语总是用动词
20、原形.Be careful.小心 Have a good time.愿你玩得开心.,B: 否定祈使句. 祈使句否定式的构成方法是在动词原形前加dont Dont laugh.不要笑. Dont be late again.不要再迟到了.,C:与please连用.可用于句首或句末. Sit down, please. 请坐. Please dont get angry. 请不要生气.,D:以let开头的祈使句. Let me help you. 让我帮助你. Lets go to the cinema. 我们一起去电影院. 这类祈使句的否定式的形式如下: Lets not hurry. let后
21、的动词要用原形.,II. 加减乘除表示法,1. “加”用plus，and或add表示；“等于”用is, equal等词表示。 2+3=? 可表示为： How much is two plus three? 2+3=5 Two plus three is five Two and three is equal to five Two and three is fiveTwo added to three is five,加减乘除表示法,2. “减”用 minus或 subtract表示 106? How much is ten minus six? 10-6=4 Ten minus six is
22、 four Subtract six from ten ,and we get four.,3.“乘”用times或multiply表示 3X4? How much is three times four? 3X4=12 Three times four is twelve Multiply three by four，we get twelve Three multiplied by four is twelve,4. “除”用divide的过去分词形式表示 164=? How much is sixteen divided by four? 1644 Sixteen divided by
23、four is fourDivide sixteen by four , and we get four.,有关数字的命令和陈述,数字命令Add 甲 and (to) 乙 甲+乙 Subtract 甲 from 乙 乙 - 甲 Multiply 甲 by 乙 甲乙 Divide 甲 by 乙 甲乙,Add 3 and (to) 9 Subtract 3 from 9 Multiply 3 by 9 Divide 9 by 3, 3+9, 9-3, 39, 93,数字的陈述甲Plus乙is /equals 丙 甲+乙= 丙甲minus乙is /equals丙甲-乙=丙甲 times乙 is /e
24、quals丙 甲乙=丙甲 divided by乙 is /equals 丙 甲乙=丙3 plus 9 is /equals 12 3 +9 =129 minus 3 is /equals 3 9 - 3 = 63 times 9 is /equals 27 3 9 =279 divided by 3 is /equals 12 9 3 = 6,练习数字命令法 A _ 2 _ 10 S _ 4 _ 5 M _ 3 _ 7 D _ 6 _ 2 用数字陈述法转换数字命令法 _ p_ _ is /equals 12 _ m _ _ is /equals 1 _ t_ _ is /equals 21 _
25、 d _ by _ is /equals 3,Now practise,dd,and,ubtract,from,ultiply,by,ivide,by,2,lus,10,5,inus,4,3,imes,7,6,ivided,2,III. 基数词和序数词,基数词:表示人或事物的数量 Eg. One ,Two 13-19都是以 teen结尾 表几十几时，在十位数和个位数之间添加连字符“-” E.g. twenty-one 21 表几百时，百位数与十位数或者百位数与个位数之间加and. three hundred and twenty 320One hundred and one 101,基数词表示
26、确切整数时，hundred /thousand后不加s E.g. 200 two hundred 当基数词表示不确定数字，如 数十个的成百的，成千上万基数词以复数形式出现 如： tens of 数十个的hundreds of 数百个的,数千个的 数百万个的,Thousands of Millions of,序数词：表示人或事物的顺序 first/second/third序数词变化规律序数词是在基数词的基础上变化而成的 多数序数词在基数词的基础上加 t hfour fourth seven seventh 第1,第2,第3要注意 one first two second three third
27、8要减t , 9要减e再加th E.g. eight eighth nine ninth 基数词以 ve结尾，变 ve 为f再加 th thirty thirtieth five fifth,IV.小数表示法,读法 小数点的左边按基数词读（当小数点左边为零时，零可省略不读），小数点读point，小数点右侧各数位单独朗读,0.5 zero point five ( point five),72.78 1.345 ,seventy-two point seven eight one point three four five,当小数数值大于1时 ，小数后的名词用复数；当小数数字小于1时，小数后面的
28、名词用单数 1.5吨 one point five tons,0.49吨 ,zero point four nine ton,Listening,Now try a quiz about numbers. Listen to the instructions on the recording, and circle the right answer.,80 49 172.66 26% 2/6$75 75% 75o 1/8 0.75 3356 65 66 90o 90% 1/9,7 2565 3881 2566 2881 2565 2881 8 1.8% 80% 18% 9 $ 5,000 $
29、50, 000 $ 50,000,000 10 30.5o 13.5o 35o,1 Which one of these is an even number? 2 Which one of these is a fraction? 3 Which one of these is a percentage? 4 Which one of these is a decimal number? 5 Which one of these is an odd number?,Tapescript,6 Which one of these is a number showing degrees? 7 My
30、 phone number is 2565 2881. 8 18 per cent of my classmates come to school on foot. 9 This ring costs fifty thousand dollars. 10 The highest temperature today was 30 point 5 degrees.,Tapescript,Writing,以说事为主的文章属于说明文，说明文主要包括地点介绍、人物介绍、知识简介、图片说明、图表说明、旅游安排等。 说明文主要以描述为表达方式，来说明某个事物的类别、性质、特征、状态或形成的原因、发生发展的过
31、程等等。写说明文应注重客观事实，用事实说话，抓住事物的特征，把地点、事物和事理解释清楚，语言简明扼要。,Traffic accidents,May asked Officer Chen about traffic accidents. Then she drew a line graph. Read the conversation and write the figures on the graph.,3,729,3,644,3,748,3,639,1 Use the verbs be, rise and fall in the simple past tense. 2 Write the
32、years and numbers of accidents in figures, not in words.,B After drawing her graph, May wrote a paragraph about it. Part of the paragraph is given here. Complete it, following these instructions:,The graph shows that there _ 3,691 accidents in 2001 in our city. In _, the number _ to _and _to _in _. In _, the number _ again to _. It _to _in _.,Traffic accidents 2001-2005,were,2002,rose,3,748,fell,3,644,2003,2004,rose,3,729,fell,3,639,2005,要点齐全，意思连贯，符合逻辑，无语法错误。,开头（1分）结尾（1分）内容要点（6分）时态（1分）字数（1分）4个错误（扣 1分）,评分标准,
