反馈
欢迎留言吐槽:
抱歉,该篇全文还没有人上传哦!我要 上传, 我要 求助
【摘要】Put a stamp on your table. Then put a glass of water on the stamp. Cover the glass with a saucer, as shown. The stamp disappears! Try to walk arotmd the glass and look into it from different sides. You will not be able to see the stamp.