B. a dead place where people dare not go
C. a terribly hot valley where people may die of heat
D. a place’s name
38.Two days later Richard Gray __________.
A. was lost in a circle
B. was drunk
C. began to search for water in the desert
D. crawled to the top of a dune to see a man
39.At last Richard Gray __________.
A. was not permitted to enter the hotel
B. got some water to drink
C. was very sorry for the waiter
D. was dying
B
You can not see any object unless light from that object gets into your eyes. Some of the things you see give off light of their own. The sun, the stars, a lighted lamp are examples that can be seen by their own light. Such things are luminous. Most of the things you see are not giving off light of their own. They are simply reflecting light that falls on them from the sun or some other luminous bodies. The moon, for example, does not give off any light of its own. It is non-luminous. You see it because sunlight falls on it and some of it reflects in our direction. So moon light is only second hand sunlight.
When you look at a book, it sends to your eyes some of the light which falls on it, and you see the book. If light could be kept out from where you are so that there would be no light for the book to reflect, then you could not see the book even with your eyes wide open.
Light travels so fast that the time in which it travels from the book you are reading to your eyes is so short as if there were no time at all. Light reaches us from the moon, which is about 380 000 kilometers away, in only a little more than a second.
40.You can see the book because_______.
A. your eyes are close to it
B. your eyesight can get to it
C. it has light of its own
D. it reflects some of the sunlight
41.The underlined word “luminous” means_______.
A. visible
B. all colors
C. giving off light
D. sunlight
42.________ have light of their own.
A. The sun and the moon
B. The sun and the stars
C.The stars and the earth
D. The moon and the earth
43.Which of the following is true?
A. All the things you can see give off light.
B. Light from the book is much shorter than that from the moon.
C. Light travels so fast that there is no time for you to read.