同等学力申硕士英语完形填空第五课
第五课
Directions : In this part, there is a passage with ten blanks. For each blank there are four choices marked A, B, C, and D. Choose the best answer for each blank and mark your answer on the Answer Sheet.
How many people can live on the face of the earth? No one knows the answer. It depends on how much food people can grow 46 destroying the environment.
More people now exist than ever before, and the population 47 growing. Every 15seconds, about 100 babies are born. Before the end of this century, the earth may 48 10 billion people!
To feed everyone, farmers must grow more food. They are trying to do so. World food production has gradually 49 over the years. In some parts of the world, 50 , the population is growing faster than the food supply. Some experts fear the world will not be able to produce enough food for a 51 that never stops increasing.
To grow more crops on the same 52 of land, farmers use fertilizers and pesticides (杀虫剂). Some plant new kinds of grains that produce more food. These things help— 53 they don't provide perfect solutions. The chemicals in fertilizers and pesticides can pollute water supplies. The new seeds developed by scientists have reached the 54 of what they can produce.
When hungry people can get no more out of 55 field, they clear trees from hills and forests for new farmland, and in doing so they expose the soil. Then rain and floods may strip the topsoil from fields. This process is called erosion. Each year erosion steals billions of tons of topsoil from farmers.
46. A. without B.by C. against D.for
47.A.ceases B.keeps C.stops D.stays
48. A. maintain B. retain C.hold D.produce
49. A. exhausted B. declined C. arisen D. risen
50. A. however B. somehow C. anyway D. furthermore
51. A. country B. nation C. population D. community
52. A. range B. amount C. number D. level
53. A. hence B. when C.but D.and
54. A. conclusion B. restriction C.goal D. limit
55. A. growing B. surviving C. remaining D. existing
