My father is the leader of a labor union.

My father was a union member of the labor union for many years.

My father is the leader of the local union.

My father serves as the president of the mutual aid society.

He is active as a member of an anonymous partnership.

He is a member of that club.

My father works at the local credit union.

He has been working as a doctor in this town for many years.

I haven't seen him for a long time.

He has been working as a doctor in this town for many years.