单项选择题
Since many insects have already become()to DDT, scientists have to look for some new insecticide
A.activeB.resistantC.toughD.gradual
单项选择题 His parents no longer worry about him. He has a good job and can live()his own now.
单项选择题 He()the medicine quickly and then drank some orange juice.
单项选择题 While studying he was financially dependent ()his wife.