1.Don't take off your clothes.It's very cold outside. 2.What were you doing at nine yesterday morning? 3.I was cleaning my room when my father arrived home. 4.What happened to Mary when she was taking a walk? 祝你开心。
Don't take off your clothes! It's cold outside What were you doing at 9:00 yesterday morning When my father got home,I was cleaning my room What happened to Mary when she walked