* A star: While the sun is a star, not all stars are the sun. There are countless other stars in the universe.

* A planet: Planets orbit stars, they are not stars themselves.

* A moon: Moons orbit planets, and are not stars or suns.

* A comet: Comets are icy bodies that orbit the sun.

* A cloud: Clouds are made of water vapor and are found in the Earth's atmosphere.

* A light bulb: A light bulb is a man-made object that produces light.

The key here is to think about what the sun *is* – a giant ball of hot gas that emits light and heat. Anything that doesn't fit that definition is a non-example.