培英中学 王健

1. Calculating machines 培英中学 王健

2. 0.82 decimal 小数

3. 45% percentage 百分比

4. a protractor 量角器

5. a pair of compasses 圆规

6. What do we use a protractor for? We use it for measuring angles.

7. What do we use compasses for? We use them for drawing circles.

8. top A b a c u s beads wires thousands hundreds tens ones bottom

9. Listen to the tape,and then read the text and discuss the questions 根据课文回答下列问题 1.What was one of the first calculating machines? 2.Do people still use adacuses today? It was an abacus. Yes they do.

10. Electronic calculator divide multiply subtract percentages add square roots

11. Computer

12. Listen to the tape, then read the text and discuss the quesstions. 2.How soon will a computer do a calculation that we could not do in our whole lifetime? 1.What can an electronic calculator do? It can add, subtract, multiply and divide. It can also calculate percentagesandsquar Nots. In aflash. 3.Are computers very powerful machines? Yes ,they are.

13. 重难点解析 so + adj. / adv. + that 从句 （结果状语从句） 1. Abacuses are so fast and accurate that people still use them today. 2. It’s so cold that no one can play outside. 3. The children played so happily that they forgot the time.

14. 4. Wendy is so young that she can’t drive. = Wendy is too young to drive. = Wendy is not old enough to drive. represent v. 表示 1. This mark represents a village. 2. The red lines on the maps represent railways.

15. 翻译下列词语： 1.算盘 2.如此···以至于 3.金属线上的珠子 4.代表个十百千 5.从···开始 6.右边的图片 7.现代电子计算器 8.它能加减乘除 an abacus so···that the beads on the wires represant ones,tens,hundreds and thousands start from the picture an the right A modern a lectronic calculalor It can add subtract multiply and divide

16. Thank you!