The sandstorm has a bad effect on human beings, but it also brings some good results. There wouldn’t have been our Chinese nation if there had been no sandstorms. Sandstorms have existed for millions of years, while the written history of human beings has lasted only 5,000 years. The Loess Plateau(黄土高原) was formed by sandstorms over millions of years. The Yellow River, while moving through the Loess Plateau, carries a great deal of sand and has formed the North China Plain. The Loess Plateau is regarded as the place where Chinese civilization(文明) began. If there had been no Loess Plateau, the North China Plain wouldn’t have existed, nor would have the Chinese civilization.

    Sandstorms don’t bring only loess to human beings. When sandstorms move from central Asia to the Pacific regions, they carry some minerals into the air, which will later fall into the ocean in the form of rain. The minerals will help some planktons(浮游生物) to survive. The planktons are eaten by small shellfish, and fish live on these small shellfish, and fish are eaten by humans. This forms a biological chain which shows a relation between humans and nature.

    So it is unrealistic to say we should stop sandstorms. What we can possibly do is to reduce their bad influence as much as we can.

59. The underlined sentence in the first paragraph probably means _________.

   A. there are many sandstorms in China

   B. the land of China was made by sandstorms

   C. sandstorms helped to form Chinese civilization

   D. the history of sandstorms was longer than that of Chinese nation

60. How does the sandstorm help to form the biological chain?

   A. The sandstorm carries lots of rain into the ocean.

   B. The sandstorm helps some minerals fall into the ocean.

   C. Some minerals directly fall into the ocean in the form of rain.

   D. The sandstorm moves from central Asia to the Pacific regions.

61. The writer thinks that _______.

   A. the sandstorm only has a bad effect on human beings

   B. sandstorms bring about lots of trouble, but we can still make use of them

   C. without sandstorms, there would be no Chinese civilization and human beings

D. sandstorms play an active role in the Chinese civilization, so we should protect them

62. The text mainly talks about _______.

   A. the history of sandstorms        B. what the biological chain is

   C. how the Loess Plateau formed    D. the good effects of sandstorms

   Astronauts’ meals have come a long way from the free-dried powders and semi-liquid pastes of decades ago,now US scientists want to grow vegetables in mini-greenhouses on the moon.

   Scientists say they are looking forward to a time when residents of future lunar or even Martian outsteps will be able to dine on fresh vegetables.Paragon Space Development Corporation has unveiled what it called the first step toward growing flowers——and eventually food—on the moon.

   This is a sealed greenhouse that looks like a bell jar encased in a 46-cm triangular aluminium frame(三角铝框架).It is designed to safely land a laboratory plant on the lunar surface,and protect it while it grows.

   The miniature greenhouse is to be launched into space by Odyssey Moon Ltd, a participant in the Google Lunar X Prize. This competition offers $20 million to any entrant(参加者) who can launch,land and operate a rover(漫游)on the lunar surface.

   Paragon officials say future testing of the“Lunar Oasis”will be driven by Odyssey’s flight schedule,which will not happen until 2012 at the earliest.

   When it does lift off the greehouse will contain the seeds of Brassica, a hardy plant related to Brussels sprouts and cabbage.Because Brassica goes from seed to flower in just 14 days,it can complete its life cycle in a single lunar night

   “Colonizing the Moon or Mars seems so far away,but it is important that we do this research now,” Paragon president Jane Poynter said.

    “It takes a long time to get a lot of research,and to get integrated,reliable efficient systems before colonists move in.”she said.

72. The article is written mainly to _________.

    A. predict the astronauts’meals in the future

    B. introduce an experiment“Lunar Oasis’’

    C. tell us the future development of astronomy

    D. focus on the human’s great progress

73. The article implies that __________.

    A. astronauts ean grow flowers in space at present

    B. Paragon and NASA will carry out the test separately

    C. Lunar Oasis is a series of experiments carried out in space

    D. the earliest testing of the Lunar Oasis may be in 2012

74. The underlined word “colonists”in the last paragraph probably has the meaning of _______.

    A. plants    B. wild beasts    C. human beings   D. scientists

75. The seeds of Brassica will be contained in the greenhouse mainly because _______.

    A. their life cycle is much shorter

    B. they are more nutritious than other food

    C. they are related to Brussels sporouts and cabbage

    D. they are very delicious

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