下列关于天体系统的叙述，正确的是（ ）
①天文学上把银河系以外的天体系统统称为总星系
②星系与银河系属于不同级别的天体系统
③银河系是天体之间相互吸引、相互绕转而形成的
④太阳系是一个以太阳为中心的天体系统．
依次填入下面文段中横线处的语句，衔接最恰当的一组是（）在对待自然的态度上，现在大概不会有人公开赞成掠夺性的强盗行径了， 。生态不仅是科学问题，而且是伦理问题，正是伦理为科学规定了界限。①但是，同为主张善待自然，出发点仍有很大分歧②我的看法是，两派都有道理，但说的是不同层次上的道理，而低层次的道理要服从高层次的道理③一派反对人类中心论，认为从根本上说，自然是一个应该敬畏的对象④一派强调以人类为中心，从人类长远利益出发，合理利用自然⑤合理利用自然是科学，不管合理的程度多么高，仍然是科学，而科学必有其界限
have, at, like, usually， watch, homework, after, play, come
I have a friend. His name is Li Daming. He often gets up ____ six o'clock in the morning. He ____ breakfast at seven. He goes to school five days a week. After school，he ____ plays games for half an hour. Look! What is he doing？He is ____ basketball. In the evening he does his ____ and he likes listening to music. He often ____TV for half an hour____ he finishes his homework. He goes to bed at ten o'clock. Do you ____ him?
