在操作挂钩梯时,梯钩应挂牢,不露()。
(A)窗台
(B)地面
(C)身体
(D)钩齿
参考答案:D
So difficult it to live in an Englishspeaking country that I was determined to learn English.
A.I have felt
B.have I felt
C.I did feel
D.did I feel
元代,意大利旅行家马可波罗来华。()