题干

It is believed that a new kind of drug ______ by the scientists and they are hopeful that they will succeed in a few months.
A.has been developedB.is being developed
C.is developingD.has developed
上一题 下一题 0.64难度 单项选择 更新时间:2015-08-27 07:20:20

答案(点此获取答案解析)