he is working in an office now .
he worked in an office yesterday .
he worked in an office for a whole day
he have just worked in an office
he has been working in an office for a hour
he had worked in an office before her
he had been working in an office when he came
he will work in an office next month
he is going to work in an office this year
he will be working in an office soon
he will have worked in an office by tomorrow
