A young man was planning to get married and asked his doctor how he could tell if his bride is a virgin. The doctor said, 'Well, you need three things. A can of red paint, a can of blue paint and a shovel..' The man was astonished and asked, 'So what do I do with these?' The doctor replied, 'Before the wedding night, you paint your one ball red and the other ball blue. If she says, 'That's the strangest pair of balls I ever saw', you hit her head with the shovel.