Explain what a light year is and why you would use it. (3-5 sentences)

a light year is the distance light traveks in one earth year. we use it to measure how far away objects are in space.

A light year is a way of measuring distance. That doesn't make much sense because "light year" contains the word "year," which is normally a unit of time. Even so, light years measure distance. You are used to measuring distances in either inches/feet/miles or centimeters/meters/kilometers, depending on where you live.