Gravity is a force that attracts objects toward each others.

The planets orbit the Sun because of the gravity of the Sun.
The Earth orbits the Sun because of the pull of the Sun’s gravity.
The Moon orbits the Earth because of the pull of Earth’s gravity.

Gravity makes objects fall to the ground.
Astronauts float in space because there isn’t any gravity there.

Gravity song by Mr. R.’s Songs for Teaching
The force of gravity pulls objects to the ground.

Gravity | The Dr. Binocs Show
Via Peekaboo Kidz