问题 选择题

α、β是两个不重合的平面,a、l、m、n是不同的直线,下列条件中,可以判定αβ的是(  )

A.aα,aβ

B.α有三个不共线的点到β的距离相等

C.l⊂α,m⊂α,lβ,mβ

D.m,l为异面直线且lα,mα,lβ,mβ

答案

若aα,aβ,则a与α,β没有公共点,但不可得到α,β没有公共点,即A不正确;

α,β相交时,三个点分居在β的两侧,满足条件,但α,β不平行,即B不正确;

根据面面平行的判定,当l,m相交时,αβ,即C不正确;

m,l为异面直线且lα,mα,lβ,mβ,由线面平行的性质,可得α内有两条相交直线与β平行,根据面面平行的判定,可得αβ,即D正确

故选D.

完形填空

阅读短文并按每小题的要求答题。

In the past twenty years, riding bicycles has become more and more popular among people of all ages. (1) Bicycles have long played an important part in the lives of American young people.But today an even greater number of adults cycle along roadsides and bicycle paths.These new riders are often trying to become fit or lose weight. They have found that bicycling is a pleasant way to stay healthy.

This is certainly good for health. But it has also brought some problems. With all these added people on the road, bicycle safety has become a matter of real importance.

Bicycle safety is mostly a matter of common sense. People should ride only on bicycle paths where they will not be badly hurt. There are also a number of rules that riders should follow,especially when riding on streets or highways. Bicyclists should never ride against the traffic,nor should they carry other people on their bicycles. They are also supposed to ride in single line on busy streets and to walk bicycles across the busy intersections(交叉路口).(2)By following these rules, bicycle riders will___ _____ stay healthy_____ ______be safe.

In one recent year, the National Safety Council reported that 34 thousand bicycle riders were hurt in highway accidents. In the same year,another six hundred riders were killed. Since the introduction of crash helmets(头盔)in 1980,the number of injuries(伤者)and deaths from bicycling accidents had gone down. Today, more and more riders realize the dangers of bicycling. They are wearing helmets and paying closer attention to cycling rules.

小题1:将画线句子(1)译成中文。

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小题2:在(2)句的空白处分别填入两个适当的词,使旬意完整、上下文通顺。

_____ _______;_______,_______

小题3:回答问题:According to the National Safety Council’s report,what’s the total number of injuries and deaths in one year?

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小题4:在文中找出与“Riders should follow a number of rules."意思相近的句子。

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小题5:在文中找出最能表达该短文主题的句子。

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判断题