Man's first real inventionand one of the most important inventions in history, (1)_____________________. The wheel is the simplest yet perhaps the most remarkable of all invention. Because there are no wheels in nature--no living things was ever created with wheel How,then,did man come to invent the wheel? Perhaps some early hunters found that (2)_________________________________________. However,the logs themselves weighed a lost. It must have taken a great prehistoric thinker to imagine two thin slices on log connected at their centers by a strong stick. This would roll along just as the logs did yet be much lighter and easier to handle. Thus the wheel and axle came into being and with them the first carts.
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作者: 木子平儿 时间: 2011-4-26 13:51
(1)was the wheel ，all transportation and every machine in the world depend on it
(2)they could roll the ... on a heavy animal through the forest on logs more easily than they could carry it作者: laura6688 时间: 2011-4-26 15:21
(1)was the wheel .Our transportation and every machine in the world depend on it
(2)they can roll the bodies of heavy animals through the force on logs more easily than they carry it作者: 陈秀玲 时间: 2011-4-28 21:30
(1)was the wheel .Our transportation and every machine in the world depend on it
(2)they can roll the bodies of heavy animals through the force on logs more easily than they carry it。作者: tdxx 时间: 2011-4-29 20:05
学习中。作者: MichaelArthur 时间: 2011-5-2 20:06
(1)was the wheel .all transportation and every machine in the world depend on it
(2)they can roll the bodies of heavy animals through the force on logs more easily than they carry it。作者: boring 时间: 2011-5-3 20:42
all transportation and every machine in the world depend on it
they could roll the body on a heavy animal through the forest on logs more easiser than they could carry it
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