13.翻譯：打開下層貨艙前，將上層甲板清潔乾淨。
(A)Clean the lower deck before open tween hold.
(B)Clean the lower deck before opening tween hold.
(C)Clean the tween deck before open lower hold.
(D)Clean the tween deck before opening lower hold.

答案：登入後查看
統計： A(5), B(7), C(16), D(16), E(0) #1199634