题目内容
Light travels（传播）at a speed which is about a million times faster than the speed of sound.In one second,light travels about 300,000 km,but sound travels only 344m.You can get some idea of this difference by watching the start of a race（比赛）.If you stand some distance away from the starter,you can see smoke come from his gun before the sound reaches your ears.This great speed of light produces（产生）some strange facts.Sunlight takes about 8 minutes to reach us.If you look at the light of the moon tonight,remember that the light rays（光线）left the moon 1.3 seconds
before they reached you.
The nearest star is so far away that the light which you can see from it tonight started to travel towards you four years ago at a speed of nearly 2 million km per minute.In some cases（在某种情况下）the light from one of tonight's stars started on its journey to you before you were born.
Thus,if we want to be honest,we cannot say "The stars are shinning（发光）tonight."We have to say,"The stars look pretty.They were shining four years ago but their light has only just reached Earth."
1.If you stand 200 meters away from a man who is firing a gun to start a race,you will find out that _____.
A. you can hear the gun before you see the smoke.
B. the sound of the gun will reach you before the man fires his gun.
C. sound does not travel as fast as light.
D. sound travels about a million times faster than light.
2.Sunlight clearly_____than the light of the moon.
A. moves less quickly B. has to travel a greater distance
C. travels much more quickly D. is less powerful
3.What does " it" in the second paragraph refer to?
A. moon light B. light rays
C. the moon D. the nearest star
4.The scientific way of saying " The stars are shining tonight" should be________.
A. the stars have been shining all the time.
B. the stars seen tonight will be shining four years later.
C. the starlight seen today could be seen four years ago.
D. the stars were shining long ago but are seen tonight.
5.The light of the nearest star you see tonight has been ______ for years.
A. away from the star B. on the moon
C. away from the sun D. on the earth
同步练习强化拓展系列答案Because six out of every 10 accidental deaths happen to Chinese children who are playing, Shanghai Johnson & Johnson Pharmaceutical (SJJP), a US?based pharmaceutical giant, is working on a Safe Kids Program to prevent injuries and deaths.
Since the Safe Kids Worldwide was set up in 1987 by Johnson & Johnson in the US, it has contributed to a nearly 40 percent decline in the child death rate from accidental injuries there.Learning from the successful experience, SJJP began the Safe Kids Program in China in 1999.
A recent survey conducted by SJJP and Safe Kids Worldwide China indicates that more than half of the responding parents didn't know how to help their children keep safe and that half of the parents didn't know about their children's motor skill development at different ages.The survey covered 3,359 Beijing, Shanghai and Guangzhou's parents with children between infancy (幼年) and 14.
Additionally, more than 40 percent of the parents didn't know how to help their children to prepare well for sports activities.For instance, they don't know how to have their children warm up or realize the importance of a playground?check before sports activities.
To help correct the problems, SJJP and Safe Kids Worldwide China have been translating and editing safety education materials, sending them to parents free of charge, and delivering free lectures in kindergartens, schools and residential communities for the last 10 years.
Currently, a special team has been set up and traveling around 12 key cities of China to popularize child sports safety knowledge and offer free training for young parents.
Though SJJP refuses to say how much it has spent on the program, it says the number in terms of money, staff and technology, is large.
SJJP was founded by Johnson & Johnson in 1995 and specializes in manufacturing and development of non?prescription medicines (非处方药) and health care foods and products.So far，its investment has exceeded $41 million.
Title: Safe Kids Program
1. | The program is intended to 2. accidental injuries and deaths. |
Background | ◇It is sponsored by SJJP, which specializes in making and 3. non?prescription medicine and health care foods and products. ◇It follows the example of the successful experience of Safe Kids. Worldwide in the US, which accounts for a 40% 4. in such injury cases. |
5. | ◇More than 50% of the parents don't know how to help keep children safe. ◇Half of the parents are not 6.of their children's motor skills. ◇40% or more of the parents fail to help their children prepare well before sports activities, such as warming up and 7. the playground. |
Solutions | ◇They have been sending safety education materials to 8.and delivering lectures in schools and communities, all for 9.. ◇A special team has been 10.and is now traveling around to popularize child sports safety knowledge and offering free training for young parents. |