中考频道为广大考生整理了初二学习资料汇总,供大家参考学习。本文主要内容是初二英语:人类探索太空。 Scientists think that there has been life on Earth for millions of year. However, we haven’t found life on other planets yet. Because none of them has an environment with air, people and things can’t grow. The Earth is a planet and it goes around the sun. The sun and its planets are called the solar system. It's a small part of our galaxy. Scientists have sent lots of spacecraft to look at other planets in our solar system, and some spacecraft have gone beyond it. However, no one has discovered any life in space yet. (责任编辑:admin) |