题干

The  first  trials  of  Aspirin  took  place  in  1899, ____ the  company  Hoffmann  worked  for ___distributing the medicine in powder form to physicians to use with patients.
A.when; beganB.which; beginning
C.when; beginningD.which; began
上一题 下一题 0.65难度 单项选择 更新时间:2019-02-20 05:43:40

答案(点此获取答案解析)