题目内容

【题目】α,β是两个不同的平面,m,n是平面α及β之外的两条不同的直线,给出四个论断:mn;αβ;nβ;mα.以其中三个论断作为条件,余下一个论断作为结论,写出你认为正确的一个命题:__________.

【答案】若①③④,则(或若②③④,则)

【解析】由面面垂直的判定,可知①③④为真;

由面面垂直的性质,可知②③④为真.

应填“若①③④,则”,或若“②③④,则”.

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【题目】Celebrating sleep

World Sleep Day, observed on 21 March, was created to bring attention to the growing number of sleep problems worldwide. Sleep is a natural part of human life, but many people in the modern world ignore its importance. As a result, sleep problems are increasingly common.

In 2002, scientists at the University of Athens in Greece conducted a survey of over 35,000 people in 10 countries around the world, including China, Belgium and South Africa. Of the people that responded to the survey, 24 percent said that they did not sleep well, and based on their responses, 31.6 percent were diagnosed with insomnia (失眠) and another 17.5 percent were diagnosed with borderline insomnia. In addition, 30.7 percent of survey respondents reported visiting a doctor for help with sleep problems and 11.6 percent said that they felt very sleepy during the day.

Overall, the survey found that many people suffer from the effects of poor quality sleep, some examples of which are being unable to fall asleep and waking up in the middle of the night. The main factors causing these problems are pressure from school or work and a fast pace of life, but noise pollution and light pollution also interfere with sleep and contribute to poor quality sleep. The surveys findings are particularly troubling because large numbers of people were found to have difficulty sleeping at night. The short-term effects of this are tiredness and trouble concentrating. If this happens for a long time, the risk of gaining weight and /span>having a heart attack may increase.

There are many things you can do to improve the quality of your sleep. First, you should have regular sleep habits. Try to go to bed and wake up around the same time each day. You also need to make your bedroom a cool, dark, quiet place to sleep so that heat, light and noise do not disturb you. At night, you should also avoid things that contain caffeine, such as chocolate, coffee, tea and many soft drinks, as caffeine may keep you from sleeping.

Getting a good nights sleep is important for everyone. By following the advice above, you can rest better at night and work better during the day.

根据短文内容,完成下列表格。

Topic

Content

World Sleep Day

Owing to 【1】________ of the importance of sleep, people celebrated World Sleep Day, bringing attention to the increasing problems of sleep.

Responses of the survey

Of 35,000 people in 10 countries in the world, there were 24% of the people【2】_______ from sleeplessness.

31.6 % were diagnosed with insomnia and another 17.5% were on the edge of insomnia.

The【3】________ of the people feeling sleepy during the day is 11.6.

30.7 % reported【4】_______ to a doctor for sleep problems.

【5】_______ causing sleep problems & their consequences

p>Under 【6】_______ from school or work, people may have sleep problems.

Poor quality sleep also 【7】_______ from noise or light pollution.

Feeling tired and sleepy, people have difficulty 【8】_______ on what they are doing.

It is likely that sleepless people easily put on weight and have a heart attack.

【9】_______ to take to improve sleep quality

Have regular sleep habits.

Make your bedroom cool, dark and quiet.

Avoid things 【10】_______ caffeine.

_______ _______ _______ _______ _______

_______ _______ _______ _______ _______

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