What time is it? 凌晨，黎明，清晨，早上

12：00 - 4：00 a.m. = 凌晨 língchén

4:00-6:00 a.m. = before sunrise, I think this technically means dawn/daybreak, 黎明 límíng

6:00 - 8:00 a.m.= early morning, after sunrise, 清晨 qíngchén

8:00 - 11:59 a.m = the morning = 早上

12:00 = 中午

12:00.00 = 正午 = high noon