7. 箱内有大小相同的6个红球和4个黑球.从中每次取1个球记下颜色后再放回箱中.则前3次恰有1次取到黑球的概率为 查看更多

 

题目列表(包括答案和解析)

阅读下列各小题,根据括号内的汉语提示,用句末括号内的英语单词完成句子。

1.Don’t be too rude to your father. Never in his life _______________ in that way up to now. (speak)

不要对你的父亲那么粗鲁,到目前为止还没有人像那样对他说话。

2.When his mother came home from work, he was lying on the sofa, ____________. (absorb)

母亲下班回家的时候,他正躺在沙发上专心致志地看书。

3.________________ different languages and cultures does a lot of good to children. (expose)

接触不同的语言和文化对孩子们大有裨益

4.I think that it is I rather than my sister _______________ for what happened. (blame)

我认为出了事不能怪姐姐而应该怪我。

5.Although house construction _________________, you can find many diverse styles in each country. (vary)

每个国家的建筑结构都不尽相同,然而在每个国家你能发现各式各样的风格。

6.With ____________, the problem that they had worked on for a long time was eventually worked out. (adopt)

由于采取了新方法,他们钻研了很长时间的问题终于解决了。

7.If he hadn’t hesitated for a moment before kicking the ball, he ______ a goal. (score)

要是他在射门前不迟疑,他就进了一球。

8.Have you ever had a case____________ getting the wrong end of the stick? (accuse)

你们有没有这样的情况:别人控告他们说他们的报道完全失真?

9._________________ is that while I am concentrating on my study, my classmates make so much noise. (put)

我不能忍受的是在我全神贯注地学习时,我的同学那么吵闹。

10._____________to you whether I like it or not, because you never listen to me. (difference)

我喜不喜欢对你来说没什么差别,因为你从来就不听我的。

 

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完成句子(共8小题,每空0.5分,满分10分)

1.这幅画稍远点看更漂亮。

The picture looks more beautiful _________ _________ _________.

2.和其他学生相比,迈克更加勤勉一些。

_______ _______ other student, Mike is more diligent.

3.一座难看的大楼把窗外的景物挡住了。

An ugly building _________ _______ _________ ______ _______ the window.

4.地球的大小是月球的49倍。

The earth is 49 _____ the ______ ______ the moon.

5.年轻时,他就有打篮球的天赋。

As a young boy, he _______ _______ ________ ______ playing basketball.

6.他的建议是办公室内不允许抽烟。

His suggestion is that no one ________ _______ _______ smoke in the office.

 

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此题要求改正所给短文中的错误。对标有题号的每一行作出判断:如无错误,在该行右边横线上画一个勾(√);如有错误(每行只有一个错误),则按下列情况改正:

此行多一个词:把多余的词用(\)划掉,在该行右边横线上写出该词,并也用斜线划掉。

此行缺一个词:在缺词处加一个漏字符号(∧),在该行右边横线上写出该加的词。

此行错一个词:在错的词下划一横线,在该行右边横线上写出改正后的词。

注意:原行没有错的不要改。

  Jim is learning what to drive a car. A                            1._______

week ago he had his first lessons. Yesterday                    2._______

his teacher took him out of on a busy road.                    3.______

It was full with cars and people. He drove                      4.______

very slowly and carefully, and he felt                               5. _______

afraid whole time. At last the lesson                                 6.______

finished and he went home. He felt tiring.                       7._____

Jim make sure that he will be able to                             8. _______

drive a car soon. Though it is difficult                               9._____

to drive it, but it is interesting indeed.                            10._____  

 

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此题要求改正所给短文中的错误。对标有题号的每一行作出判断:如无错误,在该行右边横线上画一个勾(√);如有错误(每行只有一个错误),则按下列情况改正:

    此行多一个词:用斜线(\)划掉,在该行右边横线上写出该词,并也用斜线划掉。

    此行缺一个词:在缺词处加一个漏字符号(∧), 在该行右边横线上写出该加的词。

此行错一个词:在错的词下划一横线,在该行右边横线上写出改正后的词。

注意:原行没有错的不要改。

  After I finished school, I began to look for a work.     1._______________

Now several months has passed, but I haven’t found the   2._______________

job I’m interested. Last Sunday morning, I received a3. _______________

phone call from a man called Mr. Wang. He said on       4._______________

the phone, “I hear you do well on your studies. I may5._______________

offer you a job.” I entered into his office with a beating heart.6._______________

How I wished I will go through the job-hunting talk     7._______________

and that she would take on me as an assistant.       8._______________

But to my surprised, what he said disappointed me.      9._______________

That he needed was only a model.  10._______________

 

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短文改错(共10小题,每题1分,共计10分)

对标有题号的每一行做出判断:如果没有错误,在该行的右边横线上打勾;如有错误(每行只有一个错误)则按下列情况改正:

此行多一词:把多余的词用斜线(\)划掉,在右边横线上写出该词也用斜线划掉。

此行缺一个词:在缺词处加一个漏字符号( ^ ),在该行右边横线上写出该加的词。

此行错一个词:在错的词下划一横线(__),在该行右边横线上写出改正后的词。

Last time you said you felt nervously before exams. I know         

1.__________________

the exam results are such important for students that most students

2. __________________

are nervous. My suggestion is you try to relax yourself.             

3.__________________

In fact exams are an evaluation of your studies, so there is       

4.__________________

no need to worry too much the results. I think it’s important     

5.__________________

to take a right attitude. Only before you have made good           

6.__________________

preparation for exams can you avoid suffering from the             

7. __________________

pressure of exams. You’d better go for a walk or to do            

8. __________________

some exercise before them. Besides, have enough sleep              

9.__________________

can make you full of energy. The hot bath or a glass of hot       

10.__________________

milk might help you have a sound sleep.

 

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1.C   2.A   3.B   4.D   5.C   6.B   7.D   8.C   9.B  10.A

  11.120°   12.3x+y-1=0   13.   14.10    15.100    16.(1),(4)

17.解:(1)设抛物线,将(2,2)代入,得p=1. …………4分

∴y2=2x为所求的抛物线的方程.………………………………………………………5分

(2)联立 消去y,得到. ………………………………7分

设AB的中点为,则

∴ 点到准线l的距离.…………………………………9分

,…………………………11分

,故以AB为直径的圆与准线l相切.…………………… 12分

(注:本题第(2)也可用抛物线的定义法证明)

18.解:(1)在△ACF中,,即.………………………………5分

.又,∴.…………………… 7分

(2)

. ……………………………14分

(注:用坐标法证明,同样给分)

19.

解法一:(1)连OM,作OH⊥SM于H.

∵SM为斜高,∴M为BC的中点,∴BC⊥OM.

∵BC⊥SM,∴BC⊥平面SMO.

又OH⊥SM,∴OH⊥平面SBC.……… 2分

由题意,得

设SM=x,

,解之,即.………………… 5分

(2)设面EBC∩SD=F,取AD中点N,连SN,设SN∩EF=Q.

∵AD∥BC,∴AD∥面BEFC.而面SAD∩面BEFC=EF,∴AD∥EF.

又AD⊥SN,AD⊥NM,AD⊥面SMN.

从而EF⊥面SMN,∴EF⊥QS,且EF⊥QM.

∴∠SQM为所求二面角的平面角,记为α.……… 7分

由平几知识,得

,∴

,即所求二面角为. ……………… 10分

(3)存在一点P,使得OP⊥平面EBC.取SD的中点F,连FC,可得梯形EFCB,

取AD的中点G,连SG,GM,得等腰三角形SGM,O为GM的中点,

设SG∩EF=H,则H是EF的中点.

连HM,则HM为平面EFCB与平面SGM的交线.

又∵BC⊥SO,BC⊥GM,∴平面EFCB⊥平面SGM. …………… 12分

在平面SGM中,过O作OQ⊥HM,由两平面垂直的性质,可知OQ⊥平面EFCB.

而OQ平面SOM,在平面SOM中,延长OQ必与SM相交于一点,

故存在一点P,使得OP⊥平面EBC. ……………………… 14分

 

∵底面边长为1,∴

.    ……………… 1分

平面SBC的一个法向量

∴y=2h,n=(0,2h,1).… 3分

=(0,1,0),由题意,得.解得

∴斜高. …………………………………………………… 5分

(2)n=(0,2h,1)=

由对称性,面SAD的一个法向量为n1. ………………………………6分

设平面EBC的一个法向量n2=(x,y,1),由

,得

 解得.………………… 8分

设所求的锐二面角为α,则

,∴.…………… 10分

(3)存在满足题意的点.证明如下:

. ………………………… 11分

,令与n2共线,则. ……………… 13分

.故存在P∈SM,使OP⊥面EBC.……………………… 14分

20. 解:(1)当n为奇数时,an≥a,于是,. ………………3分

         当n为偶数时,a-1≥1,且an≥a2,于是

=. …………6分

(2)∵,∴公比.……9分

. …………………………………………10分

(注:如用求和公式,漏掉q=1的讨论,扣1分)

 . ……………12分

.……15分21.解:(1)∵,∴,∴. 1分

,即,∴. …3分

①当,即时,上式不成立.………………………………………………4分

②当,即时,.由条件,得到

,解得. ……………………………………………5分

,解得.…………………………………………6分

 m的取值范围是. ………………………………………7分

(2)有一个实根.………………………………………………………………………………9分

,即

,则

. ………………………10分

 △>0,故有相异两实根

,∴ 显然

,∴,∴. …………12分

于是

                    

为三次函数的极小值点,故与x轴只有一个交点.

∴  方程只有一个实根.…………………………15分