students need enough sports and activities to do physical exercises and relax, but in some schools they are not given enough time to do outside activities. it's harmful for students' growth. teachers ask students to spend most of their time on studies. but when they feel tired and bored, students can't concentrate on studies. they are in bad health.

　　it's necessary to give students enough time to do outside activities. after good relaxation and rest, studens will work harder.

　　pay attention to students' health and growth.