"Watson, will you stop Humming that annoying tune?!" Holmes yelled as Watson gave a start.
"Oh, sorry Holmes. I just can't get it out of my head." Watson said as he got up. "I'll leave to give you some peace."
Soon, Holmes found that he couldn't stop humming the tune that Watson had been humming. Watson came in, and grinned. "So Holmes, how do you like the song?"
Holmes sighed and said, "Watson, I don't think that the Yard would give up the opportunity to hear me hum Nyan cat.