Как по будет 9: 00 / 15: 10/17: 00/21: 30

7:00 - 7o'clock (7 a.m)
7:15 - quarter past 7
7:30 - half past 7 a.m.
9:00 - 9 o'clock (9 a.m)
13:50 - 10 minutes to 2
14:00 - 2 o'clock (2 p.m)
18:10 - 10 minutes past 6
19:00 - 7 o'clock (7p.m.)
19:30 half past 7p.m
20;00 - 8 o'clock (8p.m.)
21:00 - 9 o'clock (9p.m.)
22:00 - 10 o'clock (10 p.m.)