at the present moment
goods now on sale
the now-aging dictator
they are now abroad
it could happen any time now
in these times
we now rarely see horse-drawn vehicles on city streets
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
(prefatory or transitional) indicates a change of subject or activity
Now the next problem is...
used to preface a command or reproof or request
now hear this!
now pay attention
without delay or hesitation; with no time intervening
Come here now!
in the immediate past
told me just now
'now' - used as a noun
the momentary present
Now is a good time to do it
it worked up to right now