Selective Understanding

Another example of selective understanding has come my way! I was rollerblading in the park this morning, and as I passed two teenagers, I caught the phrase "That ____ can skate." I do not know what word, offensive or neutral, went in the blank. Other happenings of this were:

"You're on _____."

"Do you _____ ______?"

This can be very confusing. Usually in these circumstances, after asking for clarification, I make a noncommittal noise and move on with the conversation.
:)