출처 : HTTP://WWW.LEARNENGLISH.DE/BASICS/TIME.HTML+TIME (1)When it's "on the hour" we say "o'clock". But only when it's on the hour.Twelve o'clockSix o'clockOne o'clockSeven o'clockTwo o'clockEight o'clockThree o'clockNine o'clockFour o'clockTen o'clockFive o'clockEleven o'clockBecause it can be difficult to say whether 12 o'clock is during the day or the night, we use two special terms.00:00 and ..