And a body in motion needs to resist external forces acting upon it that might slow it down.

运动中的身体需要抵挡外界施加的压力，不然就会被压垮。

youdao

A body at rest remains at rest, and a body in motion moves with uniform speed in a straight line, unless a force ACTS on it.

如无外力作用，静止的物体始终静止，运动的物体一直作匀速直线运动。

youdao

A body at rest will remain at rest and a body in motion remain in motion at a constant speed in a straight line, unless acted upon by an external force.

一个婴儿在休息的时候就会静静地休息，然而他们在活动的时候就会沿着直线的方向匀速活动，除非有外力作用。

youdao

One way to say it is, every body will continue to remain in a state of rest or uniform motion in a straight line.

另外一种说法是,任何物体都会继续保持静止,或匀速直线运动的状态

耶鲁公开课 - 基础物理课程节选

He used to want to fly out of self-awareness, day and night, a body in raw motion.

NEWYORKER: Still-Life

It certainly seemed to fit with previous work which had detected a wobble in the star's motion caused by a body the size of Jupiter circling in a very close orbit every 3.5 days.

BBC: We saw it too, say astronomers

As part of a broader strategy, Xsens now offers IP originally developed for professional (B2B) applications of 3D body motion tracking using wearable motion trackers for mass market application in the consumer electronics industry.

ENGADGET: Xsens teases wearable 3D body sensors that won't cost, will track an arm and a leg (video)