Mechanical analysis of revolution of basketball and choice of aiming point in shooting;
篮球投篮中球的旋转及瞄准点选择的力学分析
Relation Between the Spinning Ball and Scoring;
篮球的旋转与投篮命中率之间的关系
A knuckle ball.
（球手投出的）不旋转球
a left-arm spin bowler
投左手旋转球的投球手.
Backspin: Reverse spin imparted by striking the ball with a downward movement of the racket.
下旋：向下挥动球拍击出的旋转球，使球回转。
the revolution of the earth on its axis round the sun
地球以太阳为轴的旋转.
a baseball pitch thrown with little speed or spin.
投手投出的不旋转球。
The earth turns round at a uniform rate.
地球以不变的速度旋转。
Forward rotation imparted to a ball by a stroke, as in tennis.
上旋击球后产生的球向前旋转，例如在网球中
A forward spin on a ball resulting from such a stroke.
上旋上部击球形成的向前向上旋转
The rotational angle of a ball around its rotational axis.
转轴角-----球旋转时转轴的水平角度。
a stroke (in tennis or badminton or squash) that puts reverse spin on the ball.
（在网球或羽毛球或壁球）使球反过来旋转的击球。
The spin given to a ball by striking it on one side or releasing it with a sharp twist.
旋球击于球侧使其产生的旋转运动或急速旋转球而放出手去产生的旋转运动
To strike the upper part of(a ball), giving it forward spin.
上旋击球击打（球的）上半部分，使其向前旋转
A stroke that causes a ball to spin in a reverse direction.
削球使球向相反方向旋转的一击
The satellite slowly rotates as it circles the Earth.
卫星在绕地球旋转的同时缓慢地自转。
The earth rotates once a day on its axis.
地球绕它的自转轴一天旋转一周。
Think of Beckham's in-swinging free-kicks, his corners and central, scoring free-kicks.
想想他的旋转任意球，他的角球和中路的任意球。
Curve ball: A pitch thrown with a rotation that makes the ball curve.
曲线球：投出旋转球，使球的飞行线路呈曲线。