Man's first real inventionand one of the most important inventions in history, was the wheel All transportation and (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 they could (2)______________more easily than they could carry it. 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 (3)____________________.
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作者: zeroaoo 时间: 2012-9-3 23:06
1.every machine in the world carry down
2.road the body of the heavy animal three forest and logs
3.where and axcel can into being and whistdown the first to cards作者: susan.sui 时间: 2012-9-4 14:55
every machine in the world depends on it.
roll the body of heavy animals through the forest on logs
wheel and * came into being and * them the first carts作者: zhant220 时间: 2012-9-5 16:25
1. every machine in the world depends on it.
2. roll the batt yet they heavy the animals through the forest on logs
3. wheel and axle came into being and with them the first cars作者: 差不多小姐 时间: 2012-11-4 19:14
1. every machine in the world depends on it.
2. roll the bat yet the heavy animals through the forests on logs
3. wheel and** came into being and wait them the first cars