6:15
6:15 .
Quarter past 6 refers to the time 6:15. On a clock, the minute hand points at the 3, while the hour hand is slightly past the 6, indicating that it is a quarter of an hour after 6 o'clock. In digital format, it is displayed as 6:15.
6:15
A quarter after five, half past 6, a quarter to 7, etc...
Quarter to 10.
It means it's 6:15
You can write "quarter past six" as "6:15." This indicates that it is fifteen minutes after six o'clock. In more formal writing, you might also use "six fifteen" or "six and a quarter."
It is 06:15:00
4:45 ; Quarter to 5 5:15 ; Quarter past 5
A quarter past two!
Quarter past 12 !
Both are accepted, but "a quarter after" is preferred in formal writing.