eight o'clock 若是“在八点的时候”，借此要用at，也就是at 8 o'clock 上午八点是 8 a.m. 晚上八点是 8 p.m.
对应的英语：1) Eight o’clock and thirty eight minutes.2) Eight thirty eight.3) Thirty eight past eight.4) Twenty two. to nine.
