It's Sunday morning. The students of Class 3 are cleaning their classroom. Miss Huang is their teacher. She is working with them. The students are busy. Some are carrying water；some are cleaning the windows；others(其他人)are sweeping the floor. Zhang Hua is putting up(张贴)a map on the wall. It is a map of China. Wang Fei and Wei Qing are mending(修理)some broken chairs. The students are listening to the radio while(当……的时候)they are working. The students are very happy.