The professor together with his studentshas beenhas been(be) concerned about the side effect of the medicine over the past 2 years.
【考點】現在完成時.
【答案】has been
【解答】
【點評】
聲明:本試題解析著作權屬菁優網所有,未經書面同意,不得復制發布。
發布:2024/5/27 14:0:0組卷:1引用:2難度:0.7