试题与答案

在平面直角坐标系中,定义d(P,Q)=|x1-x2|+|y1-y2|为两点P(x

题型:填空题

题目:

在平面直角坐标系中,定义d(P,Q)=|x1-x2|+|y1-y2|为两点P(x1,y1),Q(x2,y2)之间的“折线距离”,在这个定义下,给出下列命题:

①到原点的“折线距离”等于1的点的集合是一个正方形;

②到原点的“折线距离”等于1的点的集合是一个圆;

③到M(-1,0),N(1,0)两点的“折线距离”之和为4的点的集合是面积为6的六边形;

④到M(-1,0),N(1,0)两点的“折线距离”差的绝对值为1的点的集合是两条平行线;

其中正确的命题是(    )。(写出所有正确命题的序号)

答案:

①③④

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题型:阅读理解

阅读理解。

       Dreams may be more important than sleep. Some people don't need very much sleep. But we all need to dream, scientists say.

       Dreams take up about one quarter of our sleeping time. People have several dreams each night.

Dreams are like short movies. They are usually in colour. Some dreams are like old movies. They come to us over again. That may be because the dreamer is worrying about something. Dreaming may be a way of

trying to find an answer.

       Some people get new ideas about their work from dream. But often we can't remember the dream.

Dreams can disappear quickly from memory.

       Sometimes we wake up with a good feeling from a dream.Too much dreaming can be harmful. The

more we sleep, the longer we dream. The mind is hard at work when we dream. That is why we may have a long sleep and still wake up tired.

1. The main idea of the story is that_______.

A. people need to dream

B. people like to sleep

C. dreams are like movies  

D. people don't like to dream

2. The title of the passage could be_______.

A. Secret Dreams  

B. The Longest Sleep

C. All About Dreams 

D. Why Do We Dream

3. It may be more important to dream than to________.

A. think

B. sleep

C. work  

D. speak

4. Dreams and movies are usually_______.

A. very long

B. in colour

C. about work

D. very short

5. Which of these ideas is in the story?

A. We always remember dreams  

B. All dreams are happy

B. Long dreams can make you tired

D. We don' like to dream

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