阿摩線上測驗
21. An investigation ________ into several engine break down incidents possibly linked to
contaminated fuel.
(A) have being carried out
(B) has being carried out
(C) was being carried out
(D) is being carried out
答案：登入後查看
統計： A(111), B(220), C(152), D(347), E(0) #1767631
統計： A(111), B(220), C(152), D(347), E(0) #1767631
