As is known,____ (play) team sport is popular all over the world, and participation in sporting____ (activity), such as football or basketball, is ____(benefit) to us in many aspects.

    To begin____, it can build up our bodies and help us keep fit physically,____in turn enables us____(avoid) overweight and other problems, such as high blood pressure.____ (add), it is a good way to develop some useful team skills, teamwork and strategies ____(include). Last but not ____(little), we often play sport for social reasons, for it is a good way of making new friends.

    ____, everyone should take an active part in team sports.

材料一：宋朝时期，城市开始大规模出现，首次出现了以商业，而不是以行政为中心的大城市。……店铺、朝廷办事机构与居民住宅错落相间，朝清大街几乎随处可以开设店铺。……商业街取代商业区的市，御街两旁“许市人买卖其间”，这些都是前代都市所未有过的经济生活景观。

——冯天瑜《中华文化史》

材料二：近代中国出现的新兴城市主要集中在东部地区，其中，香港、青岛等长期被列强占据：上海、天津、汉口等被辟为通商口岸，出现了崎形繁荣的商业区；近代工矿企业、商业的发展，推动了唐山、无锡等城市的兴起；郑州、石家庄等因地处铁路沿线导致较大的发展。

——周谷城《现代中国社会变迁概论》

材料三：1949～2013年新中国城市化进程示意图

——引自《1949年以来的城市化进程》

实数—2、0.3、$\frac{1}{7}$、$\sqrt{2}$、-π中，无理数的个数是                   （  ）