No offending there, this is just for my English practice.
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Although I've referred to some of articles but still was confused. Today I asked around in a chat room about this question, and finally I figured out 12-hour system. I will try to write down it here according to my personal understanding for your reference.
Let's have a look at the formation of a time first:
"12:00a.m. Feb. 2"
We can see the above information consist of two blocks, the time block and the date block. We