急性脓胸最常继发于（）

A.肺内感染

B.膈下脓肿

C.脓毒血症

D.胸膜腔积液

E.开胸手术污染胸膜腔

We have been told that under no circumstances ______ the telephone in the office for personal affairs.

A．may we use

B．we may use

C．we use

D．do we use