Classic song for singing around the campfire.
My old man's a sailor
What do you think about that?
He wears a sailor's collar,
He wears a sailor's hat.
He wears a sailor's raincoat,
He wears a sailor's shoes,
And every Saturday evening,
He reads the Sunday News.
Repeat, and each time replace "sailor" with a new occupation, the more difficult to sing, the better.

The Smothers Brothers, in their version, use

Recordings: The Smothers Brothers Think Ethnic, Mercury LP #60777
Washboard Jungle, The Brown Album