— Have you seen the film The Lord of Rings?

— Yes. When in the country, I ____ it twice. [ ]

A. saw

B. have seen

C. had seen

D. would seen

为了防止炉膛和尾部烟道再次燃烧造成破坏，常在炉膛和烟道易爆处装设( )。

A．安全阀

B．超温报警装置

C．压力表

D．防爆门