Paddy and Mick were working for their local council.
Paddy would dig a hole, then Mick would come behind him and fill in the hole.
These two men worked furiously; one digging a hole, the other filling it up again.
A man was watching from the other side and couldn't believe how hard these men were working, but couldn't understand what they were doing. Finally he had to ask them.
He said to Paddy, "I appreciate how hard you work, but what are you doing? You dig a hole and your partner comes behind you and fills it up again!"
Paddy replied, "Oh yes, it must look funny, but Liam who plants the trees is sick today."