at six
I finished work at six.
Please wake me up at six.
O Sami saiu de casa às seis.
Sami left home at six.
Eu estive trabalhando desde às seis essa manhã.
I've been working since six o'clock this morning.
She gets up at six.
Como regra eu levanto às seis, mas ontem de manhã levantei às oito.
I usually get up at six, but yesterday morning I got up at eight.
He went home at six.