A rich American went to Paris and bought a picture painted by a French artist. The American thought the picture to be very fine because he __1 底部) .The American __5 the picture this way and 6 , but still couldn’t 7 . a lot of money for it. When he came to his hotel he wanted to hang the 2 up on the wall. He 3 it for a long time, but couldn’t __4_ which was the top and which was the bottom(