青花瓷发展的黄金时代是明朝永乐、宣德时期，与郑和下西洋在时间上重合，这不能不使我们思考：航海与瓷器同时达到鼎盛，仅仅是历史的偶然吗？从历史事实来看，郑和下西洋为青花瓷的迅速崛起提供了历史契机。近三十年的航海历程推动了作为商品的青花瓷大量生产与外销，不仅促进技术创新，使青花瓷达到瓷器新工艺的顶峰，而且改变了中国瓷器发展的走向，带来了人们审美观念的更新。这也就意味着，如果没有郑和远航带来活跃的对外贸易，青花瓷也许会像在元代一样，只是中国瓷器的诸多品种之一，而不会成为主流，更不会成为中国瓷器的代表。由此可见，青花瓷崛起是郑和航海时代技术创新与文化交融的硕果，中外交往的繁盛在推动文明大交融的同时，也推动了生产技术与文化艺术的创新发展。

    作为中外文明交融的结晶，青花瓷真正成为中国瓷器的主流，则是因为成化年间原料本土化带来了民窑青花瓷的崛起。民窑遍地开花，进入商业化模式之后，几乎形成了青花瓷一统天下的局面。一种海外流行的时尚由此成为中国本土的时尚，中国传统的人物、花鸟、山水，与外来的伊斯兰风格融为一体，青花瓷成为中国瓷器的代表，进而走向世界，最终万里同风，成为世界时尚。

    一般来说，一个时代有一个时代的文化，而时尚兴盛则是社会快速变化的标志。因此，瓷器的演变之所以引人注目，还在于它与中国传统社会从单一向多元社会的转型同步。瓷器的演变与社会变迁有着千丝万缕的联系，这使我们对明代有了新的思考和认识。如果说以往人们所了解的明初是一个复兴传统的时代，其文化特征是回归传统，明初往往被认为是保守的，那么青花瓷的例子，则可以使人们对明初文化的兼容性有一个新的认识。事实上，与明代中外文明的交流高峰密切相关，明代中国正是通过与海外交流而走向开放和进步的，青花瓷的两次外销高峰就反映了这一点。第一次在亚非掀起了中国风，第二次则兴起了欧美的中国风。可见，明代不仅是中国陶瓷史上的一个重大转折时期，也是中国传统社会的重要转型时期。正是中外文明的交融，成功推动了中国瓷器从单色走向多彩的转型，青花瓷以独特方式昭示了明代文化的演变过程，成为中国传统社会从单一走向多元的例证。

（摘编自万明《明代青花瓷崛起的轨迹》）

阅读理解

    Mick Polly，an owner of a toy store，lives with his teenage daughter Carolina in Kentucky．He is known as the Bike Man．Over the past five years，Mick has built hundreds of bikes for needy kids．

    One day in 2012，a 13﹣year﹣old boy with a broken bike walked by Mick's house．"I was working in my garage（车库），and he asked if I could fix it，"says Mick，now 53．

    The boy's bike had a broken wheel．Mick sent a post（帖子） on Facebook，asking his friends if they had the needed part．One friend saw the post and gave away two used bikes．Mick took parts from each to build a new set of wheels for the boy．

    Soon after，Mick repaired a bike for the boy's brother and fixed one for his sister．Word spread，and during the year，he had fixed up lots of bikes for local kids whose parents were not able to afford new ones．

    "People are throwing away bikes day and night，"says Mick．

    Mick puts the bikes and bike parts in his garage．"I take off the good tires or the handlebars or the seats and use them，"he says．

    Up to now，the bike man has repaired hundreds of bikes and given away nearly 700newly repaired bikes．They're free，but the kids must agree to two things：They have to learn how to put waste things to good use and they have to try their best to study in school．

    If a kid's grades are low，Mick requires a teacher's note"saying that you're doing your best，"Mick says．Mick also hopes the bikes will get kids off the sofa．"When I was growing up，we all rode our bikes，"he says．"Hopefully these kids can get some exercise．"

已知θ为第二象限角，且cosθ=﹣$\frac{3}{5}$，则tan（θ+$\frac{\mathrm{\pi }}{4}$）=____ 

我们思维的独特性体现在（    ）