急求一篇150个词的英语作文题目Alien among us.

I think there must be some aliens living on some planets far from the earth,although scientists haven't find them yet.
　　Maybe they look like some kinds of animals on the earth.Maybe they are all smart and knowledgeable.Maybe they are strong… In fact,no one knows anything about the aliens.But I want to say that we can guess.And there are lots of things for us to image.For instance,we can image the situation when we meet aliens.
　　What would you do if you met aliens?
　　If I met them one day,I'll ask them some questions about something on there planet.I'm going to take them to the Great Wall.Because it's one of the symbols of the earth.
　　Do you believe it possible?