A body is in motion when it is moving from one place to another.
When is a body said to be at rest?
A body is at rest when it is not moving from one place to another.
What is necessary to give motion to a body?
Force of some kind is necessary to give motion to a body.
How long will the motion given to a body continue?
The motion will continue until it is checked.
What is necessary to check the motion of a body?
Force of some kind is necessary to check its motion.
What force is always acting so as to bring bodies to a state of rest?