单项选择题
What time can I（）the canal?
A.enter B.enter in C.enter to D.enter into
单项选择题 What’s wrong（）the winch?
单项选择题 When out of sight of land, a ship’s position can be found by using（）.
单项选择题 When visibility is reduced to about 5 miles, we say that visibility is（）.
