Newton's First Law of Motion
"An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force."
In the picture above, a person is driving a car and the car impacted by another object. The law states an object in motion will stay in motion. Therefore, if the car is in motion and it suddenly stops, the person or people that are in the car will try to keep in motion.
Newton's 1st Law of Motion for children
The object in the picture above is standing still. It will continue to stand still unless it is acted upon by an outside force.