题干

如图,在边长为a的正方形中挖掉一个边长为b的小正方形(a>b),把余下的部分剪拼成一矩形如图,通过计算两个图形(阴影部分)的面积,验证了一个乘法公式,则这个乘法公式是____

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(a+b)(a﹣b)=a2﹣b2

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    When I opened the box at my 12th birthday party, I couldn't believe my eyes. I had really gotten a mobile phone!

    As soon as I got to my school the next morning I 1off my phone and asked everyone for their2.

    It felt like I didn't even exist in that class any more. I wouldn't pay much attention to the teachers because I was too busy on my 3. Luckily I didn't get 4using it. I was pretty sure that the teacher didn't5that I stopped paying attention to her6a week later we took a test and I failed. To make matters 7, my mom had to sign the test.

    It was hard to show my mom the 8 . She was used to seeing As and Bs on my tests. Well, at last, I showed her and she couldn't 9it. She was angry.

    Weeks passed and my parents started to10the fact that I had a phone. They would say,“We have noticed that you never pay attention to us. It's like you have your own little 11now and we don't communicate as much with your phone.”

    I acted like they were wrong, but then I started to wonder if it was true that I was spending too much 12on the phone.

    A week later I tried 13 a whole day without a phone. I had so much 14because I was actually spending time with my family and paying attention to them. From that day, I had a different opinion towards phones.

    Phones really take you away from the rest of the world. I'm not saying that phones are15and not to use them, but you do have to spare some time to spend with your family. My phone took away time from my homework and from my family. I will keep using my phone, but I will have it under better control.

同类题4

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陈毅弈棋

    无产阶级革命家、军事家陈毅同志,一生多才多艺,常常在战斗和工作之余,不是赋诗以抒情怀,就是弈棋以调节身心,驱除疲劳。∥

    任新四军军长的陈毅,在苏中战斗打响后,住在苏北根据地的一个村子里。一次,他从战士那里得知村里的一位私塾先生很善下棋,便趁空闲时间只身徒步走到私塾拜访。老先生说:“我同本乡人下棋,从不动‘将’;今天你是客人,我得破例了。”于是两人对弈起来。最后,陈毅以一胜二平的比数获胜。

    过了一段时间,陈毅带领部队来村子里休整,又去找那先生下棋。这次先生声明不动“将”,与陈毅厮杀起来,结果陈毅以零比三连输三局。陈毅诧异地问:“老先生,前次你动了‘将’,我赢了;这次你‘将’不动,我反而连输三局,不知何故?”老先生答道:“前次来,我知道你是首长,又在出征前夕,不可挫其锐气;这次,我知道你在战场上取了大胜,而我在‘战场’上要使你连败三局,让你冷静一下大脑。”∥

    回忆起这件事,陈毅写了一首诗:“九牛一毫莫自夸,骄傲自满必翻车。历览古今多少事,成由谦虚败由奢。”∥

【注释】①九牛一毫:(成绩)犹如牛身上的一根毫毛,比喻微不足道。②历览:纵观;经过以往许多次的观察研究。③奢:过高地估计自己,指骄傲。