[解析]
(1)联系上文题。根据上文If you want to improve your fitness,walking is a great choice.(如果你想提高你的健康,散步是一个很好的选择)可知,本句承接上文,继续说明散步的好处。故D.It's free,simple,and adaptable to your schedule."它免费简单并且能适应你的日程安排"符合语境,故选D。
(2)联系上文题。根据标题Walk for at least 30 minutes 3 to 5 days a week.(每周至少散步3到5天,每次30分钟)可知,本段主要建议定期进行散步。故G.Going for regular walks improves your cardiovascular (心血管的) fitness gradually."定期散步可以逐渐改善心血管健康"符合语境,故选G。
(3)标题归纳题。根据本段内容If you only have a short period of time to walk,add force to work on your stamina.You can simply put a few books or solid objects in a backpack and carry that.Keep track of the amount of weight you're carrying so you can increase it gradually.(如果你只有很短的时间走路,增加力量来锻炼你的耐力。你可以简单地在背包里放几本书或一些固体物品,然后随身携带。记录你要带的重量,这样你就可以逐渐增加)可知,本段的主旨是散步的时候携带一些重量,A选项中weight对应后文weight。故A.Carry weight while walking."散步时要负重"符合语境,故选A。
(4)联系上文题。根据上文Figure out how you can introduce more walking into your daily routine.For example,you might try using the stairs instead of the elevator.(想想如何在你的日常生活中加入更多的步行。例如,你可以试着走楼梯而不是乘电梯)可知,本句与上文并列,主要是针对在日常生活中散步进行举例,故F.Or you can park further away from shops and walk the distance."或者你可以把车停在离商店远一点的地方,然后步行过去"符合语境,故选F。
(5)联系上文题。根据上文A fitness app allows you to set goals for yourself to stay active and increase your walking stamina over time. (一个健身应用程序可以让你为自己设定目标,保持活跃,并随着时间的推移增加你的步行耐力)可知,上文建议使用健身应用程序,推测本句继续说明这些程序的特点。故B.Some trackers also allow you to compete with others."一些追踪器还允许你与他人比赛"符合语境,故选B。