This document provides rules for telling time in English. Rule 1 is for telling the time at the hour, such as "It's one o'clock." Rule 2 is for times between 1-30 minutes past the hour, using "past" such as "It's twenty-five past one." Rule 3 is for times between 31-59 minutes before the next hour, using "to" such as "It's ten to five." Common terms like "half" and "quarter" are also explained.