单项选择题
A.see B.seeing C.be seen D.being seen
In the IMO SMCP the situations（）phrases using the work ...
单项选择题In the IMO SMCP the situations（）phrases using the work “can” appear it clear whether a possibility is referred to.
A.where B.when C.after D.unless
（）it is advisable to remain on a VHF channel 8, say: “s...
单项选择题（）it is advisable to remain on a VHF channel 8, say: “stand by on VHF channel 8”.
A.That B./ C.When D.What
（）we stand away from the church bell, it takes time for...
单项选择题（）we stand away from the church bell, it takes time for the sound waves to each us.
A.If B.Whenever C.Because D.Where
