问题
选择题
When a fire _________ at the National Exhibition in London, at least ten priceless paintings were completely destroyed.
A．broke off
B．broke out
C．broke down
D．broke up
答案
答案：B
短语辨析。A. 折断，中断 B.爆发火灾战争等 C. 打破，折断 D. 分手，打碎。句意：当伦敦国家展览爆发火灾时，——故选B。