太阳系的天体: the sun,planet, dwarf planet,moon 太阳系八大行星: Mercury,Venus, Earth, Mars,Jupiter, Saturn,Uranus, Neptune 内行星的构成:rock,metal 气态巨行星的构成: gas, liquid,ring (ice and dust) P星的构成:ice,rock keep...from doing sth. 阻止·.....做某事 share...with...与......合用...... wash...away 冲掉......; 冲走··..· allow sb.to do sth.允许某人做某事 out ofthis world 好得不得了;非凡 时间状语从句: When you look up high in the night sky, you mightsee lots of bright lights. 定语从句: Planets are round objects that orbit a star. 结果状语从句: It's far enough away to be not too hot, yet closeenough so it's not too cold. 被动语态: Robots called rovers have been sent to Mars. 让步状语从句: Powerful telescopes allow us to see planets andmoons even