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阅读以下说明，回答问题1-4。现有这样一个关系，用来表示某工厂工人家庭的信息。记录每个工人的工作证号、姓名和家庭住址，还包含他/她的每个孩子的身份证号、姓名和年龄，以及他／她所拥有的每部电话的电话号码和型号。已知：有一些人可能有很多部电话，这些电话可能是同一型号，也可能不是同一型号；有一些人没有电话；如果某人有电话，他的每部电话都有一个电话号码。有一些人可能有很多个孩子，有一些人没有孩子。初步设计的关系模式如下：R(身份证号，姓名，家庭住址，H身份证号，H姓名，H年龄，电话号码，型号)，其中“H身份证号，H姓名，H年龄”分别是孩子的身份证号、姓名和年龄。 [问题4] 请简要说明各范式之间的关系。(文字和图标形式皆可)

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What’s the weather like that night

A. [A] Clear with few stars in tile sky.
B. Cloudy but with plenty of stars in the sky.
Clear with lots of stars in the sky.

Conversation 1[听力原文]6-8M: When in Rome, do as the Romans do, they say.W: What do the Romans doM: They live in Rome, of course, and go to work by car or bus. But sometimes it takes too long that way because of the traffic jams, so they walk.W: In other words, the Romans do what everyone else does.M：Yes，but they do it differently．Everything is different．W: What do you meanM: Well, the climate is different for a start. I know you hate the rain. It doesn’t rain so much as it does in England. The sun shines more often.W: I envy them for the sun.M: I know. You hate the rain, don’t youW: I certainly do.M: And a Roman really loves life. They always eat spaghetti and drink wine.W: Not always, but they like a good meal. Lots of tourists go to Rome just for food.M: Sure. What does the woman hate（）

A. Sun.
B. Rain.
C. Spaghetti.
D. Wine.

[听力原文]11-15(Q11)Larry Smith is one of the rescuers on the Golden Gate Bridge. His job is to save people who attempt to jump into the sea. If the telephone rings at three in the morning, he knows it’s trouble. (Q12)Someone is threatening to commit suicide. Larry will get his things ready and in no time he will be out of the door heading to the spot. Many suicide attempts are made on the spur of the moment and lives can be saved. But if you fail, if the person jumps into the bottom of the fog, there’s no describing (Q13)how helpless you feel. Often would-be jumpers are driven to despair and see no hope of getting out of their miser). The trick is to(Q14)open a channel of communication with them. Following are some tricks that have worked. “Hey, if you’re going to jump, at least give me your mum’s phone number. So I can call and tell her.”“That’s a nice watch. If you’re going to jump. can I have it” Sometimes all it takes is the voice of the human beingyou cares. Larry estimates he has rescued(Q15)38 people in his ten years of service. What is happening if Larry’s phone rings at 3 o’clock in the morningIt means someone on the bridge is attempting to（）.

阅读以下说明，回答问题1-4。[说明] 设学校教学数据库的模式如下： S(SNUM，SNAME，AGE) SC(SNUM，CNUM，CREDIT，SCORE) C(CNUM，CNAME，TEACHER) T(TNUM，TEHCHER，POS，SAL) SNUM表示学生的学号，SNAME表示学生的姓名，AGE表示学生的年龄，CNUM表示选修课程的编号，CREDIT表示该课程的学分，SCORE表示课程的成绩，CNAME表示课程名，TEACHER表示任课的教师,TNUM表示老师的工作证号，POS表示教师的职称，SM，表示教师的收入。试定义下列完整性约束和规则： [问题3] 在关系C中把某个CNUM的值改为新的值的时候，必须同时要把关系SC中那些同样的CNUM的值也修改为新值。