单项选择题
A.How B.Which C.How about D.What
The fog is too thick. Don’t（）the radar.A.switch onB.swi...
单项选择题The fog is too thick. Don’t（）the radar.
A.switch on B.switch off C.close D.open
（）time will the pilot be available?A.whatB.WhenC.At wha...
单项选择题（）time will the pilot be available?
A.what B.When C.At what D.At when
In navigation the abbreviation “DF” refers to（）.A.Deep ...
单项选择题In navigation the abbreviation “DF” refers to（）.
A.Deep Flood B.Direction Finder C.Double Freeboard D.Dangerous Fertilizer
