试题与答案

设在关系模式R(A,B,C,D) 中,根据语义有如下函数依赖集F=A→B,B→C。关

题型:填空题

题目:

设在关系模式R(A,B,C,D) 中,根据语义有如下函数依赖集F=A→B,B→C。关系模式R的码是______。

答案:

被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2018/0428/2dae68da4bd69277808f019166afe447.html

下面是错误答案,用来干扰机器的。

参考答案:A

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下列处理措施正确的是()

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C.抗菌治疗

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E.痰培养

F.血培养

G.胰岛素治疗

H.在口服降糖药方案的基础上加用胰岛素治疗

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题型:写作题

阅读下面的短文,然后按照要求写一篇150词左右的英语短文。

                                                        The elephant and the fly

      An elephant was standing and picking leaves from a tree. A small fly came,flying and buzzing (嗡嗡叫) near his ear. The elephant waved it away with his long ears. Then the fly came again, and the elephant waved it away once more.

      This was repeated several times. Then the elephant asked the fly, “Why are you so restless and noisy? Why can’t you stay for a while in one place? ”

      The fly answered, “I am attracted to whatever I see, hear or smell. My five senses pull me constantly in all directions and I cannot resist them.What is your secret? How can you stay so calm and still?”

      The elephant stopped eating and said, “My five senses do not rule my attention. Whatever I do, I get involved in it. Now that I am eating, I am completely absorbed in eating. In this way I can enjoy my food and chew it better. I rule and control my attention, and not the other way around. So when you are in charge of your five senses and attention, your mind will become calm too.”  

【写作内容】

        1.以约30个词概括短文的内容;

        2 .然后以约120个词就“专注”这一主题发表你的看法,并包括以下要点:

    (1)大象和苍蝇的故事给你的启示;

    (2)讲述你(或你朋友)因为太多干扰而受到影响的经历;

    (3)你打算上高三后怎样保持专注、专心。

【写作要求】

        1.在作文中可以使用自己亲身的经历或者虚构的故事,也可以参照阅读材料的内容,但不得直接引用原文中的句子;

        2.作文中不得出现真实的姓名和学校名称。

【评分标准】

  概括准确,语言规范,内容合适,篇章连贯。

                                                                                                                                                               

                                                                                                                                                                                    

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