DREAM

Impossible also becomes possible in your dreams
A dream can make you fly like a bird
A dream can make you crawl on the wall
A dream can make you swim even you don't know how to swim
A dream can show you unrealistic things
A dream can show your loved ones even they are very far from you 
A dream can change between situations easily   
A dream can make you Doctor even you are an Engineer
A dream can take you to another world which is totally new for you
A dream can exist only when you stop using your brain
A dream cannot exist when you are concious