According to the survey two thirds of the areacovered by trees now and 90% of the popula

问题补充：

According to the survey, two thirds of the areacovered by trees now and 90% of the populationcontributions to the Greening Project in the city.

A. is ; has made

B. are; have made

C. is; have made

D. are; has made

答案：

A. is ; has made

B. are; have made

(答案→)C. is; have made

D. are; has made

解析：这题考察主谓 一致,当主语是分数和百分数时,谓语和它们修饰的名词一致,因为第一空的主语是 two thirds of the area所以第一空填is, ,第二空主语是90% of the population,强调具体的人,填have made.选C.