[单项选择]The passage asserts that one reason that oceans become enriched in oxygen-18 as ice sheets grow is because______.


A. water molecules containing oxygen-18 condense and fall as precipitation slightly sooner
B. the ratio of oxygen-18 to oxygen-16 in water vapor evaporated from oceans if different from that of these isotopes in seawater
C. growing ice sheets tend to lose their oxygen-18 as the temperature of the oceans near them gradually decreases
D. less water vapor evaporates from oceans during glacial periods and therefore less oxygen-18 is removed from the seawater

[单项选择]The passage asserts which of the following about commercial art
A. There are many examples of commercial art whose artistic merit is equal to that of great works of art of the past.
B. Commercial art is heavily influenced by whatever doctrines are fashionable in the serious art world of the time.
C. The line between commercial art and great art lies primarily in how an image is used, not in the motivation for its creation.
D. The pervasiveness of contemporary commercial art has led art historians to undervalue representational skills.

[单项选择]The passage mentions that one reason English and Dutch settlers planted tulips in their gardens was that tulips
A. ( were easy to grow
B. ( had become readily available
C. ( made them appear fashionable
D. ( reminded them of home

[单项选择]According to the passage, one important reason why newspapers printed daily weather maps during the first half of the twentieth century was
A. ( the progress in printing technology
B. ( a growing interest in air transportation
C. ( a change in atmospheric conditions
D. ( the improvement of weather forecasting techniques

[单项选择]According to the passage, what was one disadvantage of land expansion


A. It was inconvenient.
B. It developed too slowly.
C. It was unplanned.
D. It created a demand for public transportation.

[单项选择]

Passage Four
There is one thing that everyone wants more than anything else. Some people try to get it by making money. They think that when they have enough money to buy such things as houses, farms, and cars, they will have the one thing that everyone wants.
Other people believe that if they know enough they will find this thing. They study all their lives in search of it. Still others think that if they have power, they will find this thing. They keep telling themselves: when I am a boss, I will no longer have to search for this thing.
What is it that everyone wants more than anything else What is it that all of us keep working and striving for each day It is happiness.
Happiness is a strange thing. It does not mean the same to all men. What will make one man happy may not make another man happy. Some men say that happiness comes from helping others; other men say that happiness comes from making life more pleasant for everyone. What do y
A. when I have power, I will have happiness
B. being a boss is more important than feeling happy
C. when I become a boss, I will never search for happiness
D. boss and this thing mean the same to boss and I

[单项选择]

Passage 3
How often one hears children wishing they were grown up, and old people wishing they were young a gain. Each age has its pleasures and its pains, and the happiest person is the one who enjoys what each age gives him without wasting his time in useless regrets.
Childhood is a time when there are few responsibilities to make life difficult. If a child has good par ents, he is fed, looked after and loved, whatever he may do. It is impossible that he will ever again in his life be given so much without having to do anything in return. In addition, life is always presenting new things to the child-things that have lost their interest for older people because they are too well-known. But a child has his pains: he is not so free to do what he wishes to do; he is continually being told not to do things, or being punished for what he has done wrong.
When the young man starts to earn his own living, he can no longer expect others to pay for his food
A. life is not enjoyable since, each age has some pains
B. young men can have the greatest happiness if they work hard
C. childhood is the most enjoyable time in one's life
D. one is the happiest if he can make good use of each age in his life

[单项选择]According to the passage, what is one disadvantage of skyscrapers that have mirrored walls
A. The exterior surrounding air is heated.
B. The building materials are very expensive.
C. Construction time is increased.
D. Extra air- conditioning equipment is needed.