【答案及解析】
1．Because (if you feel stressed for too long，) it can seriously affect your body. 由第二段第二句可知答案。
2．They/Older people (who have stress for a long time) can develop heart disease, high blood pressure and other serious health problems./Heart disease, high blood pressure and other serious health problems. 由文章第二段最后一句可知答案。
3．它(压力)会使你食欲不振，不想跟你的朋友们和家人交谈/谈话/说话。/它(压力)会使你想吃得更少，不想跟你的朋友们和家人交谈/谈话/说话。
4．忙于工作或家庭生活的人可能/会感觉/感到很累/疲惫/疲倦/劳累。
5．Stress/Stress Feelings/How to Control Stress/The Ways of Controlling Stress/Tips of Controlling Stress 全文主要讲述了压力是如何形成的以及如何控制压力。
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