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如图,经过原点的抛物线y=﹣x2+2mx(m>0)与x轴的另一个交点为A.过点P(1,m)作直线PM⊥x轴于点M,交抛物线于点B.记点B关于抛物线对称轴的对称点为C(B、C不重合).连接CB,CP.

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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.