There was this couple that was married for 20 years, and every time they had sex the husband always insisted on shutting off the lights. Well, after 20 years the wife felt this was stupid. She figured she would break him out of the crazy habit. So one night, while they were in the middle of having sex, she turned on the lights. She looked down and saw her husband holding a cucumber. She gets completely upset.

"You impotent bastard," she screamed at him, "how could you be lying to me all of these years. You better explain yourself!" The husband looks her straight in the eyes and says, calmly, "I'll explain the cucumber if you can explain our three kids."