2:15 - It's quarter past two.
6:30 - It's half past six.
6:10 - It's ten (minutes) past six.
7:45 - It's quarter to eight.
7:55 - It's five (minutes) to eight.
6:20 - It's twenty (minutes) past six.
6:15 - It's quarter past six.
5:30 - It's half past five.