And the pollution problems it causes are likely to replace petroleum scarcity as the nation's most critical (5) resource problem. 1. A. more than B. more C. less D. than 2. A. damaged B. was damaged C. were damaged D. damages 3. A. conserve B. conservation C. conserving D. conservations 4. A. were placed B. was placed C. which placed D. placed 5. A. nature B. natural C. nation D. national 2. Read the text and then choose the best answer A, B, C or D. They are very much feared as hurricanes and tornadoes. They are also often called..

Exercise 8. Read the text and choose the correct option.

Erosion in America
Erosion of America's farmland by wind and water has been a problem since settlers first put the prairies and grasslands under the plow in the nineteenth century. By the 1930s,(1) _______282 million acres of farmland (2)________ by erosion. After 40 years of (3)________ efforts, soil erosion has accelerated due to new demands (4) ________ on the land by heavy crop production. In the years ahead, soil erosion
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and the pollution problems it causes are likely to replace petroleum scarcity as the nation's most critical (5)
resource problem.
1. A. more than B. more C. less D. than
2. A. damaged B. was damaged C. were damaged D. damages
3. A. conserve B. conservation C. conserving D. conservations
4. A. were placed B. was placed C. which placed D. placed
5. A. nature B. natural C. nation D. national

2. Read the text and then choose the best answer A, B, C or D.
They are very much feared as hurricanes and tornadoes. They are also often called...