the momentary present; "Now is a good time to do it"; "it worked up to right now"
used to preface a command or reproof or request; "now hear this!"; "now pay attention"
at the present moment; "goods now on sale"; "the now-aging dictator"; "they are now abroad"; "he is busy at present writing a new novel"; "it could happen any time now"
in the historical present; at this point in the narration of a series of past events; "President Kennedy now calls in the National Guard"; "Washington now decides to cross the Delaware"; "the ship is now listing to port"
in the immediate past; "told me just now"
(prefatory or transitional) indicates a change of subject or activity; "Now the next problem is..."
fraught with danger; "dangerous waters"; "a parlous journey on stormy seas"; "a perilous voyage across the Atlantic in a small boat"; "the precarious life of an undersea diver"; "dangerous surgery followed by a touch-and-go recovery"