now
‘now’
Now is usually used for contrasting the present with the past.
She gradually built up energy and is now back to normal.
He knew now that he could rely completely on Paul.
Now he felt safe.
‘right now’ and ‘just now’
In conversation and in less formal writing, you use right now or just now to say that a situation exists at present, although it may change in the future.
The new car market is in chaos right now.
I'm awfully busy just now.
You also use right now to emphasize that something is happening now.
The crisis is occurring right now.
If you say that something happened just now, you mean that it happened a very short time ago.
Did you feel the ship move just now?
I told you a lie just now.
If you intend to do something now or right now, you intend to do it immediately, without any delay.
He wants you to come and see him now, in his room.
I guess we'd better do it right now.
Be careful
Don't use ‘right now’ or ‘just now’ in formal writing.
Don't use ‘right now’ or ‘just now’ in formal writing.