an analog clock

In English, we use a 12 hour or a 24 hour clock.
We only use AM and PM with the 12 hour clock.

0:00 to 11:59 (12-11:59 AM)
12:00 to 23:59 (12-11:59 PM)

7:00 pm = 19:00 = หนึ่งทุ่ม

O'clock means x:00 (on the hour):
7 o'clock pm
7:15 o'clock pm

7:15 = seven fifteen = a quarter past seven
7:30 = seven thirty = half past seven
7:45 = seven forty-five = a quarter to eight


See thai-language.com for the full chart.

You can use a colon ':' or a period '.' with time.
15.00 = 15:00