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  • Long, long ago there was no zero. To write the number sixty-three people wrote 63. To write six hundred and three, peopl

    Long, long ago there was no zero. To write the number sixty-three people wrote 63. To write six hundred and three, people wrote 6 3. The space between six and three was there to mean "not any" tens. Sometimes people did not remember the space. It was hard to see and read.Later people used a dot to hold the space. Six hundred and three looked like this 6 · 3. But the dot was hard to see. So people put a circle around it like this 6⊙3. Then people could see the dot. They remembered the space. At last, only the circle around the dot was used. It was like a zero. This is one story of how the zero came to be used.Now zero has many important uses. Zero tells how many. Can you tell some other ways of using zero?1. Long, long ago people didn't know how to______.()A. writeB. write zeroC. write numbersD. write sixty-three2. Long, long ago if they wrote two hundred and eight, people wroteA. 28 B. 2 8 C. 228D. 2083. Later ______ was used to mean space.()A. not anyB. letter "0"C. zeroD. a dot4. People used circles _____. ( )A. to remember waysB. to remember numbersC. not to forget the space D. to mean nothing5. The story tells us ______. ()A. how zero came to be usedB. how to write zeroC. what's the use of zeroD. that zero means a dot, a circle or space
    英語(yǔ)人氣:555 ℃時(shí)間:2020-04-02 22:35:57
    優(yōu)質(zhì)解答
    1.b
    2.b
    3.d
    4.c
    5.a
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