题目

如果地球周围没有大气层，在地球上不可能目视到的是：  A．流星        B．行星            C．恒星            D．彗星 答案：A 解析: 略---I'm going to Yichun for summer vacation. It's a good place to relax.---So it is. !A. Enjoy oneself B. Have a good trip C. Thank you