阿摩線上測驗
17. ______, which is essential in learning a language, can be
difficult for beginners.
(A) Students ask questions
(B) If students ask questions
(C) Students who ask questions
(D) Asking questions
答案：登入後查看
統計： A(70), B(22), C(66), D(486), E(0) #2927374
統計： A(70), B(22), C(66), D(486), E(0) #2927374
