In an anatomy class, a professor teaches his students with the real dead body.
Every students stand around the surgery table. The dead body lie there covering by a big white blanket.
The professor starts teaching " To be a good doctor, there are two important things that everyone of you have to keep in mind. The first one is NEVER FEEL DISGUSTING WITH THE BODY"
The professor then open the blanket and slowly poke his finger deeply to the dead body's anus, spin the finger and suck it right in front of the students.
The professor said to everyone "do it Hurry!"
The students are all feeling very disgusting with the bizarre example but they all decide to do it just to satisfy the professor.
After everyone is done, the professor strongly stare at everyone and said out loud.
"Well, the second important thing for being a good doctor is that "BE OBSERVANT." If you noticed it you would see that I poke my middle finger in the anus but suck my index finger!!