A、 safety
B、 punctuality
C、 benefits
D、 A, B and C
答案:空
A、 safety
B、 punctuality
C、 benefits
D、 A, B and C
答案:空
A. A2000
B. A0000
C. A1255
D. A1277
解析:解析:provisional 临时的
A. climb
B. climbing
C. descend
D. descending
A. 100
B. 200
C. 300
D. 400
A. controller
B. pilot-in-command
C. dispatcher
D. supervisor
A. slots
B. flight levels
C. tracks
D. separations
A. Snowbound
B. Snowdrift
C. Snowman
D. Snow clearing
A. one mile
B. one and one half mile
C. two miles
D. four miles
A. passing
B. overtaking
C. crossing
D. following
A. rods
B. wands
C. lighter
D. lightening rod