题干

在德国和日本,随处可见厂房和大楼房顶的黑色“硅板”,这就是太阳能屋顶.在风和日丽的白天,“屋顶”将太阳能转化为电能,把富余的电能送入电网.上海世博会的主题是“城市,让生活更美好”,我国有关专家指出:上海没有油田和煤矿,但有两亿平方米的屋顶,不能辜负了屋顶上这片免费的阳光.上海的年平均太阳辐射量高于德国和日本,是因为(  )

A:地势高,空气稀薄

B:河湖纵横,太阳有效辐射强

C:地面祼露,比热容大

D:纬度偏低,晴天相对较多

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D

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    I serve as an educator and health care provider as well, therefore, I have worked with numerous children infected with the virus that causes AIDS. The relationships that I have had with these special kids have been gifts in my life. They have taught me so many things, but I have especially learned that great courage can be found in the smallest of packages. Let me tell you about Tyler.

    Tyler was born infected with HIV: his mother was also infected.From the very beginning of his life, he was dependent on medications to enable him to survive.When he was five, he had a tube surgically inserted in a vein in his chest.This tube was connected to a pump, which he carried in a small backpack on his back. Medications were hooked up to this pump and were continuously supplied through this tube to his bloodstream.At times, he also needed supplemented oxygen to support his breathing.

    Tyler wasn't willing to give up one single moment of his childhood to this deadly disease.It was not unusual to find him playing and racing around his backyard, wearing his medicine-laden backpack and dragging his tank of oxygen behind him in his little wagon.All of us who knew Tyler marveled at his pure joy in being alive and the energy it gave him.Tyler's mom often teased him by telling him that he moved so fast that she needed to dress him in red.That way, when she peered through the window to check on him playing in the yard, she could quickly spot him.

    This dreaded disease eventually wore down even the likes of a little dynamo (精力充沛的人) like Tyler. He grew quite ill and, unfortunately, so did his HIV-infected mother.When it became apparent that he wasn't going to survive, Tyler's mom talked to him about death.She comforted him by telling Tyler that she was dying too, and that she would be with him soon in heaven.

    A few days before his death, Tyler beckoned me over to his hospital bed and whispered, “I might die soon.I'm not scared.When I die, please dress me in red.Mom promised she's coming to heaven, too.I'll be playing when she gets there, and I want to make sure she can find me.”