There's none. They both knock on the door, but never goes in!
A chicken sedan.
Because the door was ajar!
One has a d where the other doesn't.
A washing machine doesn't follow you around after you dump a load in it.
Burglars don't knock !
Because freedom rings.
Start shouting Jehovah.
That I will open the door
Work smarter not harder people.
Someone knocking at your door for no apparent reason.
Test tickles