A man had a bad case of stuttering. He went to many doctors over the years, but none of them could help him. Finally one doctor said to him "I believe I found the reason for your stuttering".
The man asked, "Wha.. wha.. wha..what is my pro.. pro.. problem."

The doctor replied, "Your penis is very, very large. The weight of your penis is causing a strain on your larynx, and this results in your stuttering. The only solution to this is to perform a penis transplant." The man was really tired of his stuttering, so he agreed to a transplant. Several days later the doctor called the man up and informed him that they have found a suitable donor. The transplant operation was successfully performed and the man could speak without any stutter.

At first he was happy, but after a while he began to miss his large penis, and how the girls used to love it. He finally went back to his doctor and said, "Doctor, I am grateful for the opportunity you have given me to speak without a stutter, but I miss my old penis. Please find the transplant donor and tell him that we have to exchange penises back."

The doctor shook his head and replied, "That's im.. im.. im.. impo.. impossible."