Fill in the Blanks the timeOnline version explanation of time by Griselda Jiménez 1 minutes second time minutes minutes divided English first example two day hours day O`clock expression One day is into twenty - four , and each is divided once into sixty . they are divided twenty - four hours a day in halves of twelve hours each , this is known as a twelve - hour model . The twelve hours are accompanied by the a . m . and the hours of the half of the are accompanied by the term p . m . Most of the , the are not expressed individually but in groups , for which certain expressions are used . for : , this expression means " on the dot " half past , This expression means that half an hour has passed quarter past / quarter to , These expressions in are used to talk about a quarter of an hour , that is fifteen .