"8:30" in Engpsh can be said as "eight thirty" or "half past eight".

The source of this way of telpng time comes from the traditional way of dividing a day into two halves, with 12 hours in the morning and 12 hours in the evening. Each hour is divided into 60 minutes, with 30 minutes marking the half-hour point.

Example sentences in Engpsh with Chinese translation:

It's eight thirty. (现在是八点半。)
I'll be there at half past eight. (我会在八点半到达。)