Some people jump out of airplanes. They expect to fall towards the ground. This sport is called sky diving. Many people enjoy this sport. Both young and old can take part in this sport. Skydivers are pulled towards the Earth by gravity. Gravity exerts a force on the skydivers. A force is a push or pull. Some pushes and pulls can be seen.
Most forces you know require things to touch. You can push a chair. You can pull a rope. Each of these actions require you to touch something.
Gravity cannot be seen. It does not require things to touch. Gravity is an invisible force. Many things are pulled to the Earth by gravity. Can you think of some things that fall toward the Earth?
Gravity exerts a force over a long distance? Gravity holds the Moon in place. The Moon orbits the Earth every 28 days. The Earth orbits the Sun.
The Sun holds Earth in its orbit by gravity. The Sun's gravity pulls on all the planets.

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