体裁 是 说明文 还是科幻小说 字数限制 The solar system is still a mystery to humans so far. We have not known what’s exactly inside it or how old it has been or where it came from or why it is existing or when it will end its life? There are too many questions to be answered about this secret place! I want to explore in it one day in my space shutle and find out the answers! why not join me
