Question

帮忙看看下面这篇英语作文有什么语法错误或不恰当的地方 麻烦了！

Dear alien:
Scientists have sent a spaceship to Mars. However,they don’t discovered life on Mars. And astronaut have already been to themoon. Scientists have also discovered many other galaxies.It is impossible to imagine.And scientists have sent spaceships to the planet Mars to takes photos.
So I want to communicate with you.
Your friend Tom

Answer 1

Scientists have sent a spaceship to Mars . However,they haven't (改成完成时，原文时态混用了）discovered any life on Mars. And astronauts(主谓搭配不当，主语改成复数) have already been to the moon. Scientists have also discovered many other galaxies.It is impossible to imagine（这一句意思没看懂）.And scientists have sent spaceships to the planet Mars to takes photos.（最后一句和第一句是重复的，就保留一句吧。把两句合成一句）
So I want to communicate with you.