1. People who can't swim should learn to adapt in shallow water safety zone under the guidance of people with high swimming skills, and then gradually transition to deep water. People who can't swim, even if they bring impetuous tools such as lifebuoy and air cushion bed, don't swim alone in deep water, otherwise they will easily drown in complicated situations such as strong winds and waves.

2. To do gymnastics and other preparatory activities, you should gradually adapt to swimming in a short distance not far from the shore. You should not swim hard offshore, but you should have endurance.

3. Patients with heart disease, epilepsy, hypertension and other diseases are not allowed to swim in the deep water area, but they can swim in the shallow water safety area according to their physical condition, and they are supervised by special personnel.

4. Don't swim or dive rashly when the situation is unknown, because the underwater situation is unknown, you are most likely to encounter residual wooden stakes, tree roots, chaff, broken glass bottles, iron thorns, ship anchors, fishing nets, sharp stones, dense aquatic plants and so on.

Extended data:

1. We should take care of each other and care about each other. We shouldn't play or play tricks on each other and go swimming together. If someone goes ashore early, we should tell our companions that we should go home together when we go swimming together.

2. Swimming in natural swimming places (such as rivers, ponds and reservoirs) should be led by parents, relatives or teachers, with special emphasis on beginners not to swim in the wild.

3, pay attention to rest, don't swim long distances, don't stay away from your partner, if you feel unwell, tell your partner and go ashore to rest, watch your partner swim on the shore, pay attention to their safety.

4. Primary and middle school students don't swim and snorkel, and they can't compare with those who dive longer and farther. This is likely to be dangerous.

References:

Baidu encyclopedia-swimming