A dog knows what is 'no'.
About 3 replies in the top comment thread.
One's inbred, the others in bread
A rover-dose
Woof da.
He only knows up strokes
Because they're poor conductors! (I know they're called Engineers but cut me some slack, I thought of this in the 9th grade.)
Well because he had a horrible experience with windows. (credit to Neil Hamburger for this amazing joke)
Because 7 8 9