It's irritating, you know what I mean?

Don't say it, at least not once every 4.5 seconds

An athlete who used the phrase "you know" 30 times in a 135-second interview has helped win a scholarship for a middle school pupil in the United States.

Each year, a scholarship funded by a retired United States air force officer gives $1,000 to the pupil in Nebraska who can find the worst example of over-use of "you know".

This year's "You Know Contest" has been won by Evan Koontz, a pupil at Lincoln Pound Middle School - with a hit rate of one "you know" every 4.5 seconds.

He becomes the sixth recipient of a prize funded by Barney Oldfield, a 92-year-old veteran of the Second World War, who wants to highlight the way that the phrase is filling the airwaves.

Mall speak

"You know", stuck at the beginning and end of sentences, and as a pause in the middle, has been attacked for being part of teenagers' "mall speak".

Previous winners have included 13 year old Molly Kamrath who in 2000 surpassed 50 other entries with a recording of an interview which had 21 "you knows" in four minutes.

"To get 21 'you knows' in four minutes is stark testimony about how dreadfully littered we have made our beautiful English language. It deserves better treatment," wrote Mr Oldfield.

In 1999, Jessica Reinsch won the $1,000 prize with a recording of a radio interview featuring 61 examples of "you know" in 15 minutes.

Mr Oldfield has been making educational donations for many years and has given scholarships worth $3m.