阿摩線上測驗
16. Attending the workshop is _______, but it’s highly recommended for future students.
(A) required
(B) acceptable
(C) meaningful
(D) optional
答案：登入後查看
統計： A(5), B(4), C(7), D(16), E(0) #3276603
統計： A(5), B(4), C(7), D(16), E(0) #3276603
