NONE

Not a penny would they give to charity.

Not one bite did he eat.

Not a single person did they meet that day.

TOO MUCH / NOT ENOUGH

Too often do we see people struggling to make ends meet.

Too long have we waited for a change.

NEVER / NOT ANY MORE

At no time did we think the project would fail.

Never (before) have I felt so angry.

No longer can we ignore the problem.

Not in a thousand years will I go back there again.

Not once did they offer any help.

Never (again) will we attempt to intervene.

IMMEDIATELY / ONLY JUST

No sooner had one game finished than another was begun.

Barely had we got over the flu angry when we were struck down with a stomach bug.

Hardly had the policy been announced when the government came up with a new and better idea.

Scarcely had we had time to meet the villagers when we were hustled back onto the bus.

ONLY AFTER / AT A CERTAIN TIME

Not until his return did we appreciate how much we had missed him.

Only when the music stopped did people start to go home.

Only then did people start to go home.

IMPOSSIBLE / PROHIBITED

Under no circumstances should you buy products from companies which exploit workers.

On no account can drinks be taken outside.

No way can I forget what I saw there. (informal)

ONE PLACE / TIME / PERSON ETC.

Only in the capital did we feel truly welcome.

Only in the summer was it possible to open the windows.

UNUSUAL

Rarely do you find someone like that.

Seldom do we stop to think about people in poorer countries.

ADDITION

Not only is she young, she's inexperienced.

UNEXPECTED

Little did she know that trouble was coming.