阿摩線上測驗
14. Recently, there have been several outbreaks of disease like legionnaire’s syndrome, and doctors
don’t know ____.
(A) what is the cause
(B) what the cause is
(C) that is the cause
(D) that the cause is
答案：登入後查看
統計： A(22), B(266), C(3), D(3), E(0) #3099263
統計： A(22), B(266), C(3), D(3), E(0) #3099263
