Peoplehavelongnotedtheimportanceofphysicalactivity．Itcannotonlyimproveyourappearancebutalsohelptoreducetheriskofsomediseases，includingheartdisease，diabetesandevensomekindsofcancer．Butmanypeopledon'tknowhow

Question

People have long noted the importance of physical activity．It can not only improve your appearance but also help to reduce the risk of some diseases，including heart disease，diabetes and even some kinds of cancer．But many people don't know how to do exercise．
Earlier this year，the Centers for Disease Control released its first ever Physical Activity Guidelines for Americans．To get the most from your exercise plan，experts say adults should get at least two and a half hours of exercise each week．More intense（剧烈的） activities reduce the suggested amount of time to one hour and fifteen minutes．And it doesn't matter whether you exercise for short periods in five days or longer time in two or three days．
Most importantly，experts say people should choose physical activity that they find fun．This helps toguaranteethat they stay with the program．According to them，walking tops the list．More than 79 million Americans walk to stay physically fit．Another popular form of exercise is jogging（慢跑）．Jogging provides great physical conditioning for the heart and lungs．And it increases the flow of blood and oxygen in the body．Swimming is a third most popular sports activity in the United States．Swimming also presents less risk of muscle and joint injury because of the body's weightlessness in water．This makes it a great choice of exercise for people with special needs，like persons who are overweight．Dancing can also be a fun way to exercise．This is especially true for those who see exercise as a necessary evil．（坏事）
Whatever kind of exercise you choose，experts agree that you should start small and work your way up．Start by exercising ten minutes a day two times a week．After a few weeks，increase your time to fifteen or twenty minutes，and increase the number of days．
66．What is the author's purpose in writing the text？（no more than 15 words）___
67．Why should people do physical activity according to the first paragraph？（no more than 20 words）
___
68．The underlined word"guarantee"in paragraph 3 probably means___．（no more than 2 words）
69．According to the text，which is the best choice for fat people to do exercise？（no more than 5 words）___
70．What kind of physical activity do you like？Why？（no more than 20 words）___．

Answer 1

66．To give readers some advice on how to do exercise．
 67．Because physical activity can improve their appearance and help to reduce the risk of some diseases．
 68．ensure/make sure
 69．Swimming
 70．（open）I like climbing because it can not only build my body，but also improve my willpower．
66．To give readers some advice on how to do exercise．主旨大意题．  通读全文可知本文主要讲述如何锻炼身体．
 67．Because physical activity can improve their appearance and help to reduce the risk of some diseases．细节题． 根据文章第一 段It can not only improve your appearance but also help to reduce the risk of some diseases，可知人们锻炼的原因是锻炼不仅能改善你的外貌而且帮助减少得疾病的危险．
 68．ensure/make sure猜测词义题．  根据文章第三 段experts say people should choose physical activity that they find fun． 可知人们应该选择他们喜欢的运动，因为这可以确保他们坚持下去．
 69．Swimming细节题． 根据文章第三 段 This makes it a great choice of exercise for people with special needs，like persons who are overweight．可知游泳对于特殊需要的人是一个好的选择，包括那些肥胖的人．
 70．（open）I like climbing because it can not only build my body，but also improve my willpower．细节题． 根据文章第 三段walking tops the list． 可知好的体育锻炼方式有散步，慢跑，游泳，跳舞，选其中一项就可以．