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问题 选择题

下列因式分解错误的是（　　）

A．9x2-4y2=（3x+2y）（3x-2y）

B．-x2+4xy-4y2=-（x-2y）2

C．4a2b3+6ab2=2ab2（2ab+3）

D．x4-16=（x2+4）（x2-4）

答案

A、9x2-4y2=（3x）2-（2y）2=（3x+2y）（3x-2y），故此选项正确；

B、-x2+4xy-4y2=-（x2-4xy+4y2）=-（x-2y）2，故此选项正确；

C、4a2b3+6ab2=2ab2（2ab+3），故此选项正确；

D、x4-16=（x2+4）（x2-4）=（x2+4）（x2-2）（x2+2），故此选项错误．

故选：D．

阅读理解

阅读理解。

     Are you unhappy about the shape of your nose? Or do you feel that your ears are too big

or your eyes too small? Yon don't need to despair (绝望) about any of these things any longer.

They can all be put right by a surgeon. Surgeons are doctors who make sick people well by

operating on them. But some surgeons today are really beauty specialists (专家). Their job is

to make ugly or plain people beautiful. This work is called plastic surgery (整形外科). Plastic

surgeons are very popular in some countries. They make a lot of money by selling beauty to men

and women, especially women. Plastic surgery is very expensive. A new nose may cost almost

as much as a new car. Suppose I can afford to pay so much money and want to change my ugly

nose for a more handsome one. I first consult (咨询) a plastic surgeon. First of all, he will ask me

to enter a nursing home. I shall have to spend about three weeks there. The surgeon will give me

an aesthetic (麻醉剂). Then he will operate on my nose to give it the shape I want. He will put a

plaster case over it to keep it in its new shape. I shall have to spend the next week or two anxiously

wondering whether the operation has been successful or not. "Will my nose really look better?" Or

will I look uglier than before? Won't there be scars (疤痕) after the operation? What shall I do if my

 nose is not the shape I wanted? And then the great day will come. The surgeon will take off the

bandages and the plaster, and I shall see my expensive new nose! Will it be worth all the trouble

and expense? Sometimes these operations go wrong, and then the patient comes away looking

worse than before.

1. What is a plastic surgery?  

A. It is not cheap.                    

B. It is not safe.

C. It is work which can make ugly and plain people beautiful.

D. It is a plastic case.

2. Which sentence is true?   

A. It proves that the operation is worth all the trouble and expense.

B. Plastic surgery is quite profitable.

C. This kind of operation can never go wrong.

D. Beauty specialists are very popular all over the world.

3. Plastic surgery is more welcomed by ________ 

A. female    

B. beautiful people  

C. poor people  

D. male
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单项选择题

The first and most important agents of socialization are the people who care for infants. In the earliest months, messages from nurturers constitute the child’s basic understanding of the world around it. This is the infant’s first introduction to the language that shapes perception and elicits emotion.
Another powerful source of information and socialization is the friendship of peers. Peers are equals that one can deal with on the same level as oneself, whereas parents are superiors. The heavy emotional overlay of family relationships makes some kinds of learning difficult.
Much formal socialization is placed in the hands of professionals. Teachers from kindergarten on are specifically designated agents of socialization. Ideally, a teacher is one who has both knowledge and the skills to present it. During the course of teaching their subjects, classroom instructors provide role models and attempt to convey the excitement of learning itself.
In earlier times, parents, friends and teachers would comprise the list of primary childhood socializers. Children’s books, comics and magazines might also have been mentioned as sources of information on norms and role models. Today one must add three powerful indirect or nonpersonal socialization agents: radio, movies and television. Many people learn about politics, form a vision of well-being, and develop attitudes towards others from what they see on the screen and hear through the speakers.

Which of the following would be the best title for this passage

A．Childhood Socializers

B．Norms & Role Models

C．Sources of Information

D．Agents of Socialization
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