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