七点半：at seven thirty

在 exist; be living

七 seven

点 drop

半 half

现在七点半 it is half past seven

在七点 at seven o’clock = at seven

早七点半发车 the train will depart at 7

他于七点半签到上班 he signed on at half past seven

展览馆十七点半关门 refuse discussion or consideration。