You may seechild crying when he is happy or sad. So why do people cry?Scientists（do） research already. They say the body produces tears （产生眼泪） because they need them. The first kind of tears is for the eyes, and the（two） one is for the heart. They both work as cleaners. If something else like dust （灰尘） gets into your eye, tears also come into the eye to clearthe dust. If you are hurt by something, or some sad things remind yousome unhappy memories, your different feelings will produce（much） poisonous chemicals （毒素） than usual in your body, and at the same time, tears come out with them. these poisonous chemicals stay in your body for a long time, they will be bad for the heart.
In the United States, people have heart problems, （especial） men. Doctors say that heart problems have something to do with the pressure of living and working now. Maybe men suffer （遭受） more from these（ill） because they do not cry enough. So doctors encourage men（cry） more if they feel bad!
