The keys to reaching or staying at a healthy weight are regular exercise and good eating habits. Teens should get 60 minutes or more of physical activity a day. Note the word “activity”. As long as you’re getting your body moving, it doesn’t have to mean doing difficult exercise or going to the sports hall every day. All that matters is that each week you get the right balance of activity, including aerobics (有氧运动), strength building, and flexibility (柔韧) exercise. Make exercise a habit by arranging some time every day.
On days when you have soccer practice or an aerobics class, you may have no trouble exercising for an hour or more. But most of us are busy, and 60 minutes a day for exercise seems like a lot of time. The good news is that it’s OK to divide it into shorter exercise breaks throughout the day.
Just as you might have a healthy snack to stop yourself from getting hungry, exercise snacks can keep energy levels high. So get up 15 minutes early and do some stretching (伸展) activity. Walk fast or run slowly for 15 minutes after lunch. Do the same thing after school — or walk or bike home. Add to that taking the stairs, PE class, and walking between classes during the day, and you’ve probably reached your 60 minutes.
Here are five simple ways to make an exercise lifestyle change:
【小题1】The writer thinks many people probably misunderstand the word“activity” to be “_______”.  

The keys to reaching or staying at a healthy weight are regular exercise and good eating habits. Teens should get 60 minutes or more of physical activity a day. Note the word “activity”. As long as you’re getting your body moving, it doesn’t have to mean doing difficult exercise or going to the sports hall every day. All that matters is that each week you get the right balance of activity, including aerobics (有氧运动), strength building, and flexibility (柔韧) exercise. Make exercise a habit by arranging some time every day.

On days when you have soccer practice or an aerobics class, you may have no trouble exercising for an hour or more. But most of us are busy, and 60 minutes a day for exercise seems like a lot of time. The good news is that it’s OK to divide it into shorter exercise breaks throughout the day.

Just as you might have a healthy snack to stop yourself from getting hungry, exercise snacks can keep energy levels high. So get up 15 minutes early and do some stretching (伸展) activity. Walk fast or run slowly for 15 minutes after lunch. Do the same thing after school — or walk or bike home. Add to that taking the stairs, PE class, and walking between classes during the day, and you’ve probably reached your 60 minutes.

Here are five simple ways to make an exercise lifestyle change:

1.The writer thinks many people probably misunderstand the word“activity” to be “_______”.  

2.When exercising, the most important fact is ________.

3.The author advises dividing activity into shorter exercise breaks because ___.

4.What’s the best title for this passage?

The first day of school our teacher let us know someone. Looking out, we found an old woman  1  at the door. She said, "Hi, my name is Susan. I am seventy years old". While we were  2  what made her take this  3  at her age. She said with a smile. "I'm here to meet a rich husband, get  4  , have two children and travel together. " Hearing this, all of us laughed. "In fact, "she went on," I always  5  of having a college education, and now I'm getting  6  !"
After class we had chocolate and milk together. We became good   7  . I often listened to this "time machine" as she shared (分享) her  8  with me. At the end of the term we invited Susan to give us a   9  . When she was stepping up to the podium (讲台), suddenly she found she took the wrong paper. She felt a little 10   and said, "I am sorry. I am so nervous. I can't get my ready talk  11  , so I have to tell you  12  I know. "
In her speech she told us" We don't stop playing as we are old, we grow old  13  we stop playing. The secret of staying  14  , being happy and getting success is that we should laugh and find something 15   every day. I think there is a great 16  between growing old and growing up. I am seventy now. If I 17   in bed for one full year and never do anything, I'll become seventy-one. Since anybody can grow older, my  18 is to grow, up by always finding the chance in change. Growing older can't be avoided (避免) ,growing up can be 19   . It's never too late to be all you can possibly be. "
       During the four years' study, it was so easy for Susan to make friends  20  she went. In the end, the wonderful woman got the college degree (学位).
 1. A. escaped        B. appeared       C. reached      D. hurried
 2. A. finding        B. getting        C. wanting      D. wondering
 3. A. success        B. activity       C. challenge    D. work
 4. A. married        B. worried        C. excited      D. relaxed
 5. A. realized       B. made           C. knew         D. dreamed
 6. A. one            B. each           C. some         D. much
 7. A. teachers       B. friends        C. students     D. neighbours
 8. A. news           B. study          C. hope         D. experience
 9. A. lesson         B. present        C. talk         D. story
 10. A. frustrated    B. frightened     C. serious      D. painful
 11. A. again         B. back           C. down         D. away
 12. A. which         B. how            C. what         D. why
 13. A. until         B. before         C. though       D. because
 14. A. old           B. young          C. clear        D. awake
 15. A. natural       B. difficult      C. interesting  D. possible
 16. A. difference    B. change         C. pleasure     D. confidence
 17. A. lie           B. hide           C. leave        D. turn
 18. A. plan          B. mind           C. decision     D. idea
 19. A. noticed       B. chosen         C. thought      D. mentioned
 20. A. whenever      B. however        C. wherever     D. whether