分封制在周初巩固了周朝统治，在后期扩大了西周疆域；在后期却造成了分裂割据局面，瓦解了周朝的统治，造成这两种截然不同结果的根本原因是 (    )

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       （甲）金溪民方仲永，世隶耕。仲永生五年，未尝识书具，忽啼求之。父异焉，借旁近与之，即书诗四句，并自为其名。其诗以养父母、收族为意，传一乡秀才观之。自是指物作诗立就，其文理皆有可观者。邑人奇之，稍稍宾客其父，或以钱币乞之。父利其然也，日扳仲永环谒于邑人，不使学。
余闻之也久，明道中，从先人还家，于舅家见之，十二三矣。令作诗，不能称前时之闻。又七年，还自扬州，复到舅家问焉。曰“泯然众人矣。”
       （乙）初，权谓吕蒙曰：“卿今当涂掌事，不可不学！”蒙辞以军中多务。权曰：“孤岂欲卿治经为博士邪！但当涉猎，见往事耳。卿言多务，孰若孤？孤常读书，自以为大有所益。”蒙乃始就学。及鲁肃过寻阳，与蒙论议，大惊曰：“卿今者才略，非复吴下阿蒙！”蒙曰：“士别三日，即更刮目相待，大兄何见事之晚乎！”肃遂拜蒙母，结友而别。

（4﹣n²）x²﹣（n﹣2）x﹣8=0是关于x的一元一次方程，

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    I had a summer camp with my classmates for a week last year.

    Early in the morning, we gathered(聚集) at the bus station. After saying goodbye to our parents, we got on the buses. It took us more than two hours to arrive at the campground.

    We got off the buses happily. Laughing and shouting, we jumped and ran all over the place. It was the first time for us to be away from the parents. Some of us started to feel homesick(想家). However, when the night party and dances began, we felt excited again.

    The next day, everybody rushed to the boating class, hoping to be at the head of the others. At first, my friends and I worked hard, but the boat wouldn't listen to us and kept going round and round. Then the teacher taught us how to work together. After many tries, we did much better.

     Swimming class was my favourite. It was about the hottest time of a day and the best time to stay in the cool water. The swimming teacher was a funny man, and during the class he often made us laugh happily. During the week I learned a lot of new things and made many new friends. I also learned how to take care of myself.