Passage 2The keys to reaching or st

Passage 2The keys to reaching or staying at a healthy weight are regular exercise and good eating habits. Some people think exercise and good eating habits need lots of effort(努力) or planning. But that's not true. In fact, the best way to work them into our lives is by making small changes. Here's the information you need to make these healthy habits just as easy. Teens should get 60 minutes or more of physical (体力的) activity a day. As long as you’ re getting your body moving, it doesn't have to mean doing difficult exercises or hitting the gym every day. On days when you have soccer practice or a PE class, you may have no trouble in exercising for an hour or more. But most of us are busy, and 60minutes a day of activity seems like a lot of time. The good news is that it's OK to divide it into shorter “exercise breaks” in a day.Just as you might have a healthy snack to stop yourself getting hungry, exercise snacks can give you enough energy. So get up 15 minutes early and do some morning exercises. Fast walk or jog for 15minutes at lunch. Do the same thing after school ---or walk or bike home. Add to that taking the stairs, gym class, and walking between classes during the day, and you've probably reached your 60 minutes. 51. What does this passage mainly talk about? A. How to get good eating habits every day. B. How to get enough exercise easily every day. C. How to make a good plan for study. 52. How long should teens do exercise every day? A. For an hour. B. For 15 minutes. C For half an hour 53. The underlined word "it" in the 3rd paragraph refers to (指的是) A. a PE class B. soccer practice C. an hour's exercise 54. Which of the following is TRUE according to the passage? A. We should do some difficult exercises every day. B. We should eat less and make ourselves hungry every day. C. Exercise snacks can provide us with enough energy 55. We can probably find this passage in _________. A. a magazine B. a poster C. a story book