单项选择题
A. had worked too hard in pleasing his fans B. had fallen victim to public opinion C. had been an extremely sentimental guy D. had experienced both joys and sorrows
A. consider DDT’s positive uses B. continue to keep DDT illegal C. remove some restrictions on DDT use D. study DDT’s impact on human health
A. the cheap labor of the students B. to show high academic standard C. to attract enough full-time professors D. the talented hands to help with research