comet

n. 慧星

Comets move around the sun like planets, but in long oval course.

彗星象行星一样绕太阳运转，然而其轨道呈狭长的椭圆形。

If I had binoculars, I could see that comet clearly.

如果我有望远镜，我就可以清楚地看见那颗彗星。