深圳牛津英語(yǔ)八上B本Unit3 abacus

1、Unit 3AbacusWord learningMatch the words with their meanings on the right.beadrodwoodenrepresentuppercalculateactiveframe(e)a very small ball(g)a thin light stick(h)made of wood(f)to stand for(a)above middle(d)to solve number problems(b)functioning (c)a supporting structrueDo you know abacus? Lead i

2、n It is the Worlds oldest computer.It is also called suanpan.It is a tool that people use to calculate numbers.What is a Chinese abacus made of? It is made of beads, thin rods and a wooden frame.Reading Scan para 1 and answer.beadsthin rods a wooden frameWhen did people start using the abacus? Over

3、4,000 years ago.Reading Can you name the parts of abacus in English? beads in the two part have different values bead roda wooden frame a horizontal bar upper partlower parttwo beads on each roadeach bead represents five five beads on each rodeach bead represents one decimal value十進(jìn)制onetenhundredSca

4、n para 1 and answer.How to use abacus?Scan para 2 and answer.Reading first, _ the number.The bead above the bar move _.The bead blow the bar move _.second, _ numbers.To represent one, push _ one bead on the first rod below the barTo represent five, move _ one bead on the first rod above the barclean

5、updownrecorddownupIs it easy to use abacus?Scan para 2 and answer.Reading No, it isnt. Its _ and _ to add or subtract numbers with an abacus, but it take more _ and _ to do multiplication and division. A good user can even calculate square roots!quickeasytimepractice In 2013, the Chinese abacus was

6、officially listed as a World Intangible Cultural Heritage by UNESCO.Thinking Some people say doing calculations in your head helps to exercise your brain and using an abacus or a calculator makes your brain lazy. Do you agree? Why or why not?(Possible answer)I agree. I think our brains also need exe

7、rcise just like our bodies do. Calculations are a great way to exercise our brains because we have to concentrate and think carefully in order to make no mistakes. This brain exercise can help us to focus when we do other activities too.Thinking Compare an abacus with an electronic calculator.(Possi

8、ble answer)An abacus is made of rods and beads, yet an electronic calculator has a display screen and a keyboard.In terms of material, an abacus is usually made of wood and bamboo, while an electronic calculator is made of metal and plastic .Depending on size and material , both an abacus and an ele

9、ctronic calculator can be light or heavy. When using an abacus, you need to remember rules and count how many beads you have moved . When using an electronic calculator, you simply push the buttons and the result will be shown on the display screen.Thinking Do people still use abacus to calculate nu

10、mbers? Why do you think people do that?(Possible answer)I still see people using abacuses to calculate, especially in old Chinese pharmacies.There are many reasons why people make that choice.For a pharmacist, it is a tradition to use an abacus to calculate the dosage of Chinese medicine. People hav

11、e done that for hundreds of years. Moreover, it is faster to add and subtract using an abacus than an electronic calculator. Since most calculation in a pharmacy only requires simple addition and subtraction, an abacus is preferred. Finally, using an abacus is cheaper. It is usually more expensive to buy a computer or an electronic calculator. An abacus also helps to save electricity.Read the passage loudly Key notes beads and rods算珠和檔a woodent frame 一個(gè)木框a horizontal bar 一根橫梁divide into把分成decimal value 十進(jìn)制the