阿摩線上測驗
5. When vessels sail along the coasts, ______ observations at interval are required to
safeguard the safety of navigation.
(A) regular
(B) odd
(C) queer
(D) casual
答案：登入後查看
統計： A(448), B(27), C(47), D(101), E(0) #3209670
統計： A(448), B(27), C(47), D(101), E(0) #3209670
