阿摩線上測驗
129 By the time the technicians arrived, the problem _____ already been resolved.
(A) has
(B) have
(C) had
(D) having
答案：登入後查看
統計： A(365), B(75), C(849), D(14), E(0) #3772637
統計： A(365), B(75), C(849), D(14), E(0) #3772637
