Answer:
What goes up the hill and down the hill, And spite of all, yet stand still?
There are 5 sisters in a room: Ann is reading a book, Margaret is cooking, Kate is playing chess, Marie is doing the laundry. What is the fifth sister doing?
On which day of the year do fewest people die?
What man can shave 10 times a day and still have a beard?
Why can't Kevin, who is now living in Canada, not be buried in the USA?
I appear in the morning. But am always there. You can never see me. Though I am everywhere. By night I am gone, though I sometimes never was. Nothing can defeat me. But I am easily gone.