LCFD：FLIGHT/DATE/LEGS中LEG最大为（）个航节。
A.10
B.15
C.20
D.25
参考答案：B
There are five pairs ,but I’m at a loss which to buy. [ ]
A.to be chosen
B.to choose from
C.to choose
D.for choosing
气瓶存放处（）内禁止明火，禁止与易燃物、易爆物同间存放。
A.7m
B.8m
C.9m
D.10m
