单项选择题
A.will meet with
B.met with
C.would meet with
D.would have met with
单项选择题 If an airplane circles a vessel 3 times，crosses the vessel’s course close ahead while rocking the wings，and heads off in a certain direction，what does this indicate?（）
单项选择题 Distress signals may be（）.
单项选择题 By regulation，orange smoke distress signals will expire not more than how many months from the date of manufacture?（）