Light travels________ than sound．

　　　 A．much fast　　　 B．far fast　　 C．much faster　　 D．more taster

閱讀理解

　　Light travels at a speed (速度) which is about a million times faster than that of sound. In one second, light travels about 300,000 kilometers, but sound travels only 340 meters. You can get some idea of this difference by watching the start of a running match. If you stand quite far away from the starter (發(fā)令員), you can see smoke come from his gun before the sound reaches your ears.

　　The fast speed of light produces 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 (射線) left the moon 1. 3 seconds before they reached you. The nearest star is so far away that light which you can see from it tonight started to travel to you 4 years ago at a speed of nearly 2 million kilometers every minute. The light from some of tonight's started on its journey towards you even before you were born.

　　So, if we want to be honest (誠實(shí)的), we can not say, “The stars are shining brightly tonight.” We have to say. “The stars look nice. They were shining four years ago but their light has just reached our earth.”

1．The best title of this passage is ________.

[　　]

A．Light Travels Faster Than Sound

B．Stars Are Far Away From Us

C．The Speed of Light

D．How Light Rays Travel

2．If you stand 200 meters away from a man who is lifting a gun to 

start a running match, you will find out ________.

[　　]

A．light travels a million times faster than sound

B．the smoke of the gun gets into your sight after the sound of the gun-shot

C．sound travels less fast than light

D．the sound of the gun reached you at the same time with the light of the smoke

3．Sunlight obviously (明顯的) ________ than the light of the moon.

[　　]

A．has to travel a greater distance (距離)

B．moves less quickly

C．travels much more quickly

D．is less powerful

4．The scientific way of saying ``The stars are shining brightly 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 stars which were shining long ago but are seen tonight

D．the starlight seen tonight could be seen four years ago

5．The light of the nearest star you see tonight has been ________ for years.

[　　]

Light travels at a speed which is about a million times faster than the speed of sound. You can get some idea of this difference by watching the start of a race. If you stand some distance(距離) away from the starter, you can see smoke from his gun before the sound reaches your ears.

This great speed of light produces some strange facts. Sunlight(太陽光) takes about 8 minutes to reach us. If you look at the light of the moon tonight, remember that the light rays left the moon 1.3 seconds before they reached you. The nearest star is so far away that the light that 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, the light from one of tonight’s stars had started on its journey to you before you were born.

Thus, if we want to be honest, we can’t say, “The stars are shining tonight.” We have to say instead, “The stars look pretty. They were shining four years ago, but their light has only just reached the earth.”

1.Light speed is ______ sound speed.

A. as fast as                          

B. a million times slower than

C. about millions of times faster than     

D. about a million times faster than

2. 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 sound before you see the smoke

B. the sound does not travel as fast as light

C. the sound will reach you before the man fires

D. sound travels about a million times faster than light

3.Sunlight obviously(顯然的) ______ than the light of the moon.

A. has to travel a greater distance          

B. moves less quickly

C. travels much more quickly            

D. is less powerful

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 shine four years later

C. the stars were shining long ago but seen tonight

D. the starlight seen today could be seen four years ago