The following discussion (讨论)took place(发生) between a father and his nine-year-old son."It's unfair (不公平)，Dad. Mum wants me to make. my bed，but I don't know how.""It's time for you to learn. Where are your clean sheets (床单)?”“I don't know.”What do you mean you don't know? You need to take care of your things.”"Where are Jack's sheets?"*the father called his wife.“Right next to ours，" the wife answered..After a moment, the father asked slowly, "Where are ours?"'