When I was in high school, our physics teacher asked us to make a paper airplane of any shape. The only object(目标) was to get this paper airplane to fly as far as possible. I learned some paper airplane making skills so I made the best plane that I could and it flew far.
One boy named David made the greatest but simplest paper airplane of all. He stood there at the starting line with only a piece of paper. Some classmates laughed at him. Moment later, he crumpled(弄皱) it up into a ball, and threw it out.
To our surprise, he beat the class without any difficulty. Some of the students got mad and said that he cheated(欺诈). Thy physics teacher said, "I said it could be any shape. A paper ball is a shape. " I still consider this classmate as a genius(天才).