CRTSⅠ型双块式轨枕混凝土强度达（）MPa时方可脱模。
A、40
B、42
C、45
D、48
参考答案：A
— Listen! There is a strange noise over there.
— There _____ some dangerous animals. Let's run away. [ ]
A. will be
B. could have
C. will have
D. might be
对航空器局部安保检查，重点是离机旅客的前后3排。（）
