1、Why do people never feel hungry on a beach?
为什么在沙滩上的人永远不会觉得饿？

2、What's the difference between a monkey and a flea?
猴子和跳蚤有什么区别?

3、What hangs on the wall without nail or string?
什么东西不用钉子和线就可以挂在墙上??