下列哪些因素可以导致手术室内燃爆事故的发生（）
A.可燃性全麻药
B.水
C.静电
D.助燃剂
E.可燃物质
参考答案：A, C, D, E
We spent hours driving and another few hours waiting, only _________ that the plane would be delayed until midnight.
A．to be told
B．having told
C．to have been told
D．told
在中国引起回归热的病原体是（）
A.木通包柔体
B.委内瑞拉包柔体
C.赫姆斯包柔体
D.波斯包柔体
E.拉迪什夫包柔体
