Stress is the feeling you get when you're really worried about something． This is the kind of worry that troubles you for hours，or even days．It makes you feel (11)，scared(恐惧的)，or angry． You may find it difficult to eat and sleep，or you might eat and sleep much(12) than usual． Stressing out will lead to serious 'problems like heart illness．(13)  not all stress is bad for you． The good kind (14) your body and mind alert(机敏的) and can make you perform better，like when you're giving a speech to your class or running to the finish line．

What causes stress? Do you know(15) your dad is worried about the bills，or your mom is unhappy? Because they're stressed out! There are lots of things in your life that ,(16) cause stress-having too much homework，taking a test in a subject that you are not good (17) ，or hearing your parents argue!

There are some ways to (18) stress． If you're stressed out，try these quick and easy

ways to relaxt Take part in sports and out-of-class activities． Try to get at least eight hours of sleep every night． Eat a healthy，balanced (19) that includes all kinds of food． Talk with your close friends，family members or teachers: It'll make you feel better，and (20) may be able to give you advice and help you solve your problem．

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