what is white when it is dirty 猜猜what是什么

what is white when it is dirty 猜猜what是什么 it is clean when it is black.it is dirty when itis white.what is it 智力测试What is black when it is clean and white when it is dirty? What is clean when it is black and dirty when it is white? What is black when it is clean white when it is dirty? what is black when it is clean and white when it is dirty是----- What is black when it is clean and white when it is dirty? What is biack when it is clean and white when it is dirty? what is biack when it is ciean and white when it is dirty?(翻译意思） What is clean when it is blanck and dirty when it is white? 【what is clean when it black ,and white when it is dirty. 猜谜语：It is clean when it is black.It is dirty when it is white.What's it 英语：读一读,想一想,猜一猜What is black when it is clean and white when it is dirty?It is a ( ). When I am clam ,I am black .When I am dirty,I am white.What am 智力题 英语谜语：when I am white,I am dirty.when I am biack,I am ciean.what am What are you looking,Jim?I was making shhopping list when rhe telephone rang.There is many rea in the white box. What is black when it is clean and white when it is dirty?求求啦!我弟的寒假作业. what is black when it is clean and white when it is dirty?用英语怎么回答