求英语作文 My invention 80词左右

There are many inventions in the world,but my favorite invention is the computer.As a student the computer helps me a lot.With the computer,I can find lots of information I need .I can read books,know the latest news and watch movies.I can play games or listen to music when I am tired.It is easy to communicate with my friends.I often chat with them through e-mails and QQ.I think in the future ,the computer will be used by everyone.

Now, more and more serious environmental problems. So, I want to invent a green robot. Its first function is to purify the air, the first is it filled with an air purifier, will first inhaled air, and...