The picture shows six of the eight planets in the solar system.这幅图标示了太阳系八大行星中的6颗。...careful observation of the movement of the planets...对行星运动的仔细观测There was no gainsaying the astronomer's knowledge about the planets...

Does life exist on other planets?其他行星上有生命吗？Which planets can sustain life?哪些行星可以维持生命的存在？Asteroids, also known as " minor planets ", are numerous in the outer space.小行星, 亦称为 “ 小型行星 ”, 在外太空中不计其数....

planets的音标：planets的英式发音音标为：[p'lænɪts]planets的美式发音音标为：[p'lænɪts]...

n.行星( planet的名词复数 )，地球（尤指环境）...