An invisible man is here to see you
Nurse: Doctor, there is an invisible man in your waiting room.

Doctor: Tell him I can't see him now. Next.

A Hot Day
It was a stifling hot day and a man fainted in the middle of a busy intersection.

Traffic quickly piled up in all directions, so a woman rushed to help him.

When she knelt down to loosen his collar, a man emerged from the crowd, pushed her aside, and said, "It's all right honey, I've had a course in first aid."

The woman stood up and watched as he took the ill man's pulse and prepared to administer artificial respiration.

At this point she tapped him on the shoulder and said, "When you get to the part about calling a doctor, I'm already here."