Earl's Long Name

This guy was driving down the highway and was pulled over by the cops. The cop asked the man for his name and the guy replied:

- Earl.

- You got a last name, Earl?

- Nope. It's a long story, Officer.

- I got time.

Earl sighs and says:

- Well, Officer, at first I was known as Earl Doo-Daa. I was going to school to become a doctor, and I did, so I was known as Earl Doo-Daa, MD. I got bored just being a doctor so I went to dental school, graduated, and became Earl Doo-Daa, M.D., D.D. After a little more time I fooled around with this girl and got VD. So I was known as Earl Doo-Daa, MD, DD, with VD. When the medical board found out about my VD they took away my MD so I was known as Earl Doo-Daa, DD with VD. The dentistry board also found out about the VD and took away my DD making me Earl Doo-Dah with VD. Finally, the VD took away my Doo-Dah so I'm now just Earl.