Exemption

Three Corkmen went to America where they were immediately called up for Army service. In the hope of being exempted, each of them pleaded unfitness on medical grounds. The first Corkman explained that he was shortsighted. He was sent right up to the front line where he would have no difficulty in seeing the enemy.
The second Corkman explained that one of his legs was shorter than the .other. He was sent to fight on hilly ground.
The third Corkman decided to be more subtle - he had all his teeth extracted. He was exempted because he had flat feet.