问题 问答题

黑色花为什么很少见我们生活在姹紫嫣红、色彩缤纷的世界里,但是我们看到的黑色花却很少.植物学家对四千多种花的颜色进行了统计,发现只有8种黑色花,而且还不是纯正的黑色,只是偏紫色而已.为什么会出现这种现象呢?原来花的颜色与太阳光及花瓣反射、吸收光有关.太阳光是由七种颜色的色光(红、橙、黄、绿、蓝、靛、紫)组成.光的颜色不同,其热效应也不同.有色不透明物体反射与它颜色相同的光,吸收与它颜色不同的光,黑色物体吸收各种颜色的光.花瓣比较柔嫩,为了生存,避免受高温伤害,它们吸收热效应较弱的光,而反射热效应较强的光.这就是我们看到红、橙、黄色花多,而蓝、紫色花较少的缘故.若吸收七种光,受高温伤害就更大,花也更难生存,所以黑色花很少.

请根据短文,回答下列问题:

(1)红色花反射什么颜色的光?吸收什么颜色的光?

(2)短文中提到“光的颜色不同,热效应也不同”,那么你认为红色光与蓝色光哪种色光的热效应强呢?

(3)材料中没有提到白色花,请你推断白色花反射什么颜色的光,吸收什么颜色的光.

答案

(1)红花只能反射红光,其它色光都被红花吸收了.

(2)花瓣比较柔嫩,为了生存,避免受高温伤害,它们吸收热效应较弱的光,而反射热效应较强的光,所以红光比蓝光的热效应强.

(3)白花反射所有色光,不吸收任何色光.

故答案为:(1)红花只能反射红光,其它色光都被红花吸收了;

(2)红光比蓝光的热效应强;

(3)白花反射所有色光,不吸收任何色光.

阅读理解

As computers become all the more popular in China, Chinese people are increasingly relying on computer keyboards to input Chinese characters. But if they use the computer too much, they may end up forgetting the exact strokes(笔画)of each Chinese character when writing on paper. Experts suggest people, especially students, write by hand more.

Do you write by hand more or type more? In Beijing, students start using a computer as early as primary school. And computer dependence is more wide-spread among university students. Almost all their assignments and essays are typed on a computer.

All the students interviewed say they usually use a computer.

It's faster and easier to correct if using a computer. And that's why computers are being applied more and more often to modern education. But when people are taking stock in computers increasingly, problems appear.

"When I'm writing with a pen, I find I often can't remember how to write a character, though I feel I’m familiar with it."

"I'm not in the mood to write when faced with a pen and paper."

Many students don't feel this is something to worry about. Now that it's more convenient and efficient to write on a computer, why bother to handwrite?

Many educators think differently. Shi Liwei , the headmaster of a famous primary school in the capital said "Chinese characters enjoy both practical and aesthetic(审美的) value. But those characters typed with computer keyboards only maintain their practical value. All the artistic beauty of the characters is lost. And handwriting contains the writer's emotion. Through one's handwriting, people can get to know one's thinking and personality. Beautiful writing will give people a better first impression of them"

To encourage students to handwrite more, many primary schools in Beijing have made writing classes compulsory(必修的)and in universities, some professors are asking students to turn in their homework and essays written by hand.

小题1:Which of the following can best serve as the title of the passage?

A.The Importance of Handwriting and Typing.

B.To Type or To Hand Write

C.Writing By Computer Will Replace Writing By Hand

D.Practical and Aesthetic Value of Chinese Characters.小题2:The students interviewed prefer to write using a computer mainly because______.

A.they are usually asked to e-mail their Homework and Essays

B.they can correct the mistakes they make quickly and conveniently

C.they find it not easy to remember how to write a character

D.computers have become a trend and fashion in China.小题3:Which of the following statements is NOT TRUE of the advantages of handwriting?

A.Handwriting contains the writer's emotion.

B.The writer’s thinking and personality are shown in his or her handwriting,

C.Handwriting can impress people well and build one’s self-confidence

D.Chinese characters enjoy both practical and aesthetic value.

填空题