The first invention of mankind was the wheel. The invention of the wheel is probably the

most important invention of all time. Without the wheel, the world simply wouldnt exist as we know. 【M1】______ The invention of the wheel was at the root of the Industrial Revolution, which it would take a long time to get there. 【M2】______ Although no wheel forms are found in nature; undoubtedly the earliest "wheels" were smooth logs which were used for moving weights over the earths surface. It is a mystery so as to who 【M3】______ invented the first wheel. No one recorded who was or when it 【M4】______ happened; but when the first inventor has placed a wheel on an axle, mankind began to roll on one place to another. This type of wheel 【M5】______ have been found among Egyptian relics dating back due to 2,000 B.C, 【M6】______ and earlier Chinese civilizations are credited with independent invention of the same mechanism. The wheel so fascinated man that he has spent centuries building machines around them; yet in over 4,000 years he has not 【M7】______ changed its basic design. All about us we see the spinning shafts, gears, flywheels, and rotors are the descendants of the first wheel. 【M8】______ The roaring propeller of an aircraft engine, the whirling wheel of a giant steam turbine, and the hairspring of a tiny watch are examples of the motorized motion which characterizes our 【M9】______ mechanism world. It is hard to conceive of continuous motion 【M10】______ without the wheel.

【M1】