13. Walk-ins are welcome but appointments are ______.
(A) preferred
(B) prefer
(C) preferring
(D) preference
答案:登入後查看
統計: A(501), B(33), C(68), D(38), E(0) #2388438
統計: A(501), B(33), C(68), D(38), E(0) #2388438