—What happened to you the other day?

—I　　to Beijing,but I missed my flight.

A．would fly

B．was flying

C．had flown

D．flew

主动脉瓣关闭不全X线检查的特征是（）

A.心腰凸出

B.右室增大

C."摇椅式"搏动

D.肺门舞蹈

E.上腔静脉增宽