历年英语四级的考试阅读理解部分2_大学英语阅读

历年英语四级的考试阅读理解部分2

　　can make new models of artificial hearts available on the market in 10 to 20 years

　　30. The new models of artificial hearts are expected _____.

　　to have a working life of 10 or 20 years

　　to be set fully in the patients chest

　　to be equipped with an external power source

　　to create a new passage for infection

　　31. The word them in Line 7, Para. 2 refers to _____.

　　doctors who treat heart diseases

　　makers of artificial hearts

　　Americas health-care programs

　　new models of artificial hearts

　　32. Some people feel that _____.

　　artificial hearts are seldom effective

　　the country should not spend so much money on artificial hearts

　　the country is not spending enough money on artificial hearts

　　Americas health-care programs are not doing enough for the nations health

　　Passage Four

　　Questions 36 to 40 are based on the following passage:

　　A rapid means of long-distance transportation became a necessity for the United States as settlement spread ever farther westward. The early trains were impractical curiosities, and for a long time the railroad companies met with troublesome mechanical problems. The most serious ones were the construction of rails able to bear the load, and the development of a safe, effective stopping system. Once these were solved, the railroad was established as the best means of land transportation. By 1860 there were thousands of miles of railroads crossing the eastern mountain ranges and reaching westward to the Mississippi. There were also regional southern and western lines.