you should be able to listen to the rhythm and pick up what's going on.
(and do i really have to list the lyrics?)
Dad has a knife
He's stabbing his wife
Mom has a saw
She's sawing off her own jaw
Mom without a jaw
and Dad without a wife
They're making awful plans
You'll get cancer in your hand
The bass part during the bridge is a basic minor blues bass line. It's just a bunch of E's followed by “G E G A” on the bottom string.
A for a while, and lift your middle finger on and off the G string for the bit of melody.