下述哪项除外，其余均为肺门病变的基本X线表现（）
A.肺门增大
B.肺门缩小
C.肺门移位
D.肺门结核
E.肺门密度增高
参考答案：D
曳引机吊装离地面()时,应停止起吊,确认安全后方可继续吊装.
A.30mm
B.50mm
C.10cm
D.15cm
After they _________ cleaning the classroom, they________ home yesterday.[ ]
A. finished; went
B. had finished; went
C. finished; gone
D. had finished; had gone
