Bows and arrows, are one of man's oldest weapons. (1)___________________. The ordinary bow or short bow was used by early all early people. This bow bad limited power and short range. However, (2)___________________. The long bow was most likely discovered when someone found out that a five-foot piece of wood made a better bow than a three-foot piece. Hundreds of thousands of these bows were made and used for three hundred years. However, not one is known to survive today. We believe that a force of about one hundred pounds was needs to pull the string all the way back on a long bow. (3)____________________. In fact, more changes have taken place in a bow in the past 25 years than in the last 7 centuries. Today, bow is forceful. It is as exact as a gun. In addition, it requires little strength to draw the string. (4)____________________. In indoor contests, perfect scores from 40 yard are common. The invention of the bows itself ranks with discovery of fire and the wheel. It was a great-step-forward for man.
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作者: susan.sui 时间: 2014-2-10 11:31
they give early man an effective weapon to kill his enemies.
man overcame these faults by learning to track his targets at a close range.
for a long time, the bow was just a bent stick and string.
morden bows also have precise aiming devices.
