In Spanish, time is arrayed slightly different in the syntax. There are only a few differences.
To say the time, you would say the number of hours and then the number of minutes. Observe:
Es tres y diez. It is 3:10.
P'm and a'm are abbreviated the same way.
To say the hour:
Tengo una cita a las tres. I have an appointment at three. The "las" refers to the Spanish word horas, meaning hours.