智力测试What is black when it is clean and white when it is dirt

智力测试What is black when it is clean and white when it is dirt What is clean whenit isblack,and it is white when it is dirt what is black when it is clean and white when it is dirty是-- What is clean when it is black and dirty when it is white? 英语翻译4.What is black when it is clean and white when it is di What is black when it is clean and white when it is dirty? what is black when it is clean and white when it is dirty?用英 脑筋急转弯：1 What's black when it is clean and white it is dirty? 英语趣味问和答 What is black when it is clean and white when it is What is black when it is clean white when it is dirty? That is black when it is clean and white when it is dirty 猜谜语 1 What is biack when it is clean and white when it is di