我国某地农村曾流传一首民谣：“社员干活听敲钟，一天干活真稀松。队长哨子吹半天，社员还不到地边。”改变这种状况的措施是(　　)

阅读理解

    What's your hobby? Reading，playing sports or going to the movies?Hassan has an interesting hobby．He likes collecting tropicalfish(收集热带鱼)! He keeps this hobby for 7 years．Now he is 14．There is a big aquarium(养鱼缸)in his room．It is from his parents for his 13th birthday．There are many fish in it．All of the fish are cute and beautiful．

    Hassan often travels around the world(周游世界)with his family．He loves it because he can see the underwater world in many places．He always loves the colorful underwater world．Under the water,he can see lots of tropical fish．Sometimes he can see sharks(鲨鱼)．He wants to keep one or two small sharks in an aquarium,but he can't do it at home．So Hassan goes to help in the zoo on the weekend．There he can see a lot of sharks and some other big fish．Hassan likes working in the zoo，because he can work with his favorite animals and leam more about them．

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下图是元世祖忽必烈，1260年他继承汗位，建年号“中统”，这一年号体现了忽必烈(　　)