Protecting his Turf

Jennifer: “I think we are going to grill burgers for the tennis team lunch I’m hosting.”
John: “How will you grill burgers if I’m not there?”
Jennifer: “Well, I did manage to graduate college with a 4.0. I think I can figure out how to cook raw meat with fire.”
John: “You had to pull out the 4.0, huh?”
Jennifer: “You know it. I knew that would come in handy one day.”