The teacher had given the class an assignment. He stresses the importance of this particular assignment, and that no excuses will be accepted except illness (with a medical certificate) or a death in the immediate family (with a note from that member). A wise student pipes up: 'What about extreme sexual exhaustion, sir?' The class breaks up laughing, and when they settle down the teacher responds with: 'Well, I guess you'll have to learn to write with your other hand.'