1、One astronomical unit equals the distance from the earth to the sun.
一天文單位等于從地球到太陽的距離。

2、One astronomical unit is the distance between the Earth and the sun, about 93 million miles.
一個天文單位是地球與太陽的距離，大約9300萬英里(1.5億公里)。

3、An astronomical unit is the distance between Earth and our sun.
一個天文單位是地球與太陽之間的距離。

4、One astronomical unit is the distance between the Earth and the sun.
一個天文單位等于地球到太陽之間的距離。