The teacher had given the class an assignment.

The teacher had given the class an assignment. He stresses the importance of this particular assignment, andthat 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."