49.——You didn't wait for Mr.Black last night,did you?——No,bu
49.——You didn't wait for Mr.Black last night,did you?——No,but we ____.He didn't retur详解
49.——You didn't wait for Mr.Black last night,did you?
——No,but we ____.He didn't return home at all.
A.couldn't have B.needn't have C.didn't need to D.should wait have