What does she shake?
Her shoulders.
How many arms do you have?
I have 2 arms.
What is this?
.............
How many shoulders do you have?
I have two shoulders.
What is this?
............
What is wrong?
..................
How many heads do you have?
I have one head.
How many knees do you have?
...............
What is this?
.................
What does he slide on?
He slides on his knees.