参加右肺门影构成的结构有（）
A.右下肺动脉
B.升主动脉
C.上腔静脉
D.右下肺静脉
E.以上都不是
参考答案：A
—He was nearly drowned once.
—When was __________?
—__________ was in 1998 when he was in middle school.[ ]
A. that; This
B. this; This
C. this; It
D. that; It
______ is impossible if you put your heart into it. [ ]
A. Anything
B. Something
C. Everything
D. Nothing
