He's staring at your shoes instead of his own.
Cleaver! EDIT: Also Sharp, knew about this one but I like Cleaver better.
I don't like sprouts!
Humphrey. (I was told this joke by an actual dad, it was his response to one of my jokes)
Babe, it's a valve!
So he could look at others' faces.
Vans of der Waals
Finnish hymns
When you arrive at the international airport you are American. There is a room that changes your nationality. When you enter this room you are Russian, when you leave this room you are Finnish, and while inside European. What room is it?
He stares at shoes while he talks to you.