See a cell phone cover that you like on Taobao? Forget about placing an order, paying the bill online and waiting for days for it to be delivered to you. In the near future, you'll be able to get it in minutes just by hitting "print" on your computer. You might find it hard to believe that you could actually "print" an object as you would a picture. But it is not that hard to understand how it would work. Just as a traditional printer sprays (喷) ink onto paper line by line, modem 3-D printers spread material onto a surface layer by layer, from the bottom to the top, gradually building up a shape.

    Instead of ink, the materials the 3-D printer uses are mainly plastic, resin (树脂) and certain metals. The thinner each layer is — from a millimeter to less than the width of a hair —the smoother and finer the object will be. This may sound like a completely new technology, but the truth is that 3-D printing has been around since the late 1980s. Back then, it was barely affordable for most people, so few knew about it.

    Last year, though, saw a big change in the 3-D printing industry — printers became much cheaper. For example, 10 years ago a desktop 3-D printer might have cost £20,000, while now they cost only about £ 1,000, according to the BBC. Taken out of the factory and introduced to more diverse and common uses, 3-D printing can create just about anything you can think of --- flutes (笛子), bikinis, jewelry, aircraft parts and even human organs. In fact, scientists from Cornell University in New York have just made an artificial ear using a 3-D printer, according to Science Daily. The fake ear looks and acts exactly like a natural one.

    However, as 3-D printing becomes more common, it may bring about certain problems —such as piracy. "Once you can download a coffee maker, or print out a new set of kitchen utensils (餐具) on your personal 3-D printer, who will visit a retail (零售的) store again?", an expert in 3-D printing told Forbes News. Even more frightening, what if anyone in the world could use a 3-D printer to print out a fully functioning gun?

—I often practice ________ the violin.

近代日本两次侵华给中华民族带来了深重灾难。如今的中日关系能否正常发展已成为维系东亚、太平洋地区和平与安全的重中之重。阅读下列材料，回答后面问题。
材料一   甲午战争是一个命运转折点。随着北洋舰队的全军覆没，中国腐朽之极的封建制度走到了它的尽头。
——《人民日报：从甲午战争的废墟上崛起》
（1）甲午战争给中国代来了什么影响？
材料二   无论“日本军队此后如何在东北寻衅，我方应予不抵抗，力避冲突。”
——蒋介石给张学良密电
（2）材料二中当时中国发生了什么重大事变？蒋介石对这一事变持什么态度？
材料三   我们亲爱的将士们：双十二抗日救国运动……为争地盘吗？不是。为泄私愤吗？也不是……我们主张的核心是集合全国各党各派的力量，以民众的总动员，去抗日救国。”
——《张、杨告东北军、十七路军将士书》
（3）材料中的“双十二抗日救国运动”是指什么历史事件?这一事件的和平解决有何意义?
材料四   2014年2月27日下午，十二届全国人大常委会第七次会议经表决通过了两个决定，将9月3日确定为中国人民抗日战争胜利纪念日，将12月13日设立为南京大屠杀死难者国家公祭日，悼念惨遭日本侵略者杀戮的死难同胞。
——摘编自新华网
（4）根据材料四并结合所学知识，指出我国设立“南京大屠杀死难者国家公祭日”的重大意义。
材料五 日本右翼势力美化侵略战争，为军国主义招魂的活动一直没有停止过，应引起中国人民的高度警惕。日本曾接连发生右翼分子篡改中学历史教科书和内阁成员参拜供奉有甲级战犯牌位的靖国神社的事件。
——华东师大版《中国历史》“课外学史”
（5）结合材料五，日本右翼势力不断发表伤害中国乃至亚洲人民感情的言论，对此你有何看法？你认为日本政府应该如何正确处理中日关系？