What does it mean to keep warm when it gets cold?

When the weather cools down, pay attention to keep warm, which means that both children and adults should do a good job of personal warmth. If you are a child at school, you must wear a hat, down jacket, mask and gloves, and be fully armed from top to bottom to avoid catching a cold. This can avoid freezing hands, feet and ears and avoid frostbite. The same is true for adults, if they work in the day shift.