At\to have breakfast (lunch, dinner)
At first\first sight
at peace (war)
at present
at sunset
at table
at home (work)
at night
by day
by accident
by air (water, sea, land)
by chance
by heart
by means of
by mistake
by name
by order of
by post (airmail)
by tram (train, boat, bus, coach)
day after day
day and night
face to face
hand in hand
in sight
in fact
in case
in cash
in common
in conclusion
in\on demand
in debt
in detail
in time
in vain
on credit
on deck (board ship)
on fire
on sale
out of breath
out of doors
out of rule
to ask permission
to be in charge\on duty
to be in town
to be on strike
to go to town
to keep in touch
to go to school
at school
to go to bed
to be in bed
to shake hands
to lose sight
to declare war
to pass judgement