1.   Gravity is the force that makes the planets move around the sun.

2.   Gravity is the force which makes the planets move round the Sun.

3.   He posited that each planet moved in a perfect circle.

4.   Kieran suggest we say, instead of saying the planets move round in orbit we should say the planets orbit the sun.

5.   As a planet moves around a star, its gravity pulls on the star, causing it to wobble slightly.

6.   Johannes Kepler, who discovered that the planets move in elliptical paths around the Sun, was motivated by a mystical love of musical harmonies.

7.   The planets move as they should and the sun shines.

8.   The planets move at different speeds in their individual lanes, occasionally overtaking and lapping each other.