7:00 - seven o'clock
5:01 - five oh one
6:45 - six forty-five
8:21 - eight twenty-one
10:30 - ten thirty
11:15 - eleven fifteen
1:00 - one o'clock
2:48 - two forty-eight
3:55 - three fifty-five
12:00 - twelve o'clock
4:25 - four twenty-five
7:40 - seven forty