How long his dog ? [ ]
A. has, been dead
B. has, died
C. has, been died
D. has, dead
答案:A
契丹 * * 的建立者是[ ]
A.耶律阿保机
B.元吴
C.赵匡胤
D.完颜阿骨打
行V形天窗作业应具备的条件?