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- At the same time the speed of walking became fast, the two support tine and the distance of the center of gravity move became short. 行走时步速加快，双支撑时间缩短，步宽和重心左右移动的距离都明显减小。
- Depending on the onwards, it pointed out that the arms swinging have a far-reaching influence on take-off acceleration of the body, moreover, the more acceleration distance of arms swinging, the more final speed of the center of gravity of the body. 由此指出，手臂摆动对身体起跳加速力的贡献率很大，并且，手臂加速摆动的距离越长，身体重心速度的增加越明显。
- What is the force of gravity at sea level? 海平面的地球引力多大?
- The force of gravity pulls things towards the earth's centre. 地心吸力把物体吸向地心。
- The speed of this aircraft is very high. 这架飞机的速度非常快。
- The hurricane has a speed of 73 miles per hour. 飓风每小时73英里。
- The speed of a runaway horse count for nothing. 脱缰之马的速度毫无价值。
- He discoursed impressively on Newton's theory of gravity. 他讲述了牛顿的引力定律，给人以深刻的印象。
- The speed of light is an important constant. 光速是一个重要的常数。
- The speed of the toy boat is variable. 玩具船的速度是可变的。
- The force of gravity makes things fall to earth. 地心引力使物体落向地面。
- The symbol for the speed of light in a vacuum. 表示真空中光速的物理符号
- Newtow conclusively established the law of gravity. 牛顿确定了万有引力定律。
- The plane defied the laws of gravity. 这架飞机经受住了引力定律。
- Rapidity or speed of motion; swiftness. 迅速，快速运动的快速或速度; 迅速
- The earth is round because of gravity. 地球是由于重力而成为球形的。
- When did the first measurement of the speed of sound take? 第一次测量声速是在什么时候？
- We have to submit to law of gravity. 我们必须服从引力定律。
- The pull of gravity depends upon size, or, more accurately, upon mass. 引力的拉力取决于物体的大小，或者更确切地说，取决于质量。
- Raindrop fall at a speed of about500 to1,000 feet a minute. 雨点以每分钟大约五百到一千英尺的速度下降。
