First of all, all the expressions of time can be said directly in order, such as the title, which is 1944.
Secondly, it is bounded by half a minute (that is, 30 minutes). If it is less than 30 minutes, the past time (in minutes) is used. If it is 19: 20 (less than 30 minutes), it is 9: 20. If it exceeds 30 minutes, connect minutes with to (60 minutes). If 19:44 (greater than 30), the minute is 60-44= 16, which means six to twenty.