He has his hair cut once a month.
Somehow you must find a way to finish this work in one month.
My watch gains two minutes a month.
How often do you wash your car a month?
He comes here once a month.
They were born one month apart in 1970.
You should call on your parents at least once a month.
How much is the monthly rate?
A lunar month is shorter than a calendar month.
You're a month behind in your rent.