Mr. Smith found that gas         from the pipe when he came back because we forgot to switch off. But at last we were lucky to escape           .

A．escaped, being punished

B．was escaping, being punished

C．escaped, punishment

D．was escaping, punishing

一戴用全口义齿患者，在做侧方咬合时，平衡侧义齿基托翘动、脱落，其最可能的原因是（）

A.正中不平衡

B.侧方不平衡

C.前伸不平衡

D.垂直距离过高

E.义齿固位差