单项选择题 Mariners proceeding across the main routes are（）to do so at as wide an angle as practicable.

单项选择题 Mariners are reminded that they should proceed in the general direction indicated by the arrows or，if（）a lane，they should do so as nearly as practicable at right angles to it.

单项选择题 Mainly east 3 or 4 partly cloudy to overcast occasional rain（）slowly south moderate or good.