New York

TWENTY-ONE years ago last month, Friends made its debut on NBC, to almost instant acclaim and popularity, beginning a 10-year run that ushered into the culture various styles and mannerisms - Jennifer Aniston's haircut, most notably - in a way that now rarely occurs, because the television landscape has become drastically more diffuse.

On Friends, characters emphasised their adjectives (with "very" and "really" and "so") to such an extent that the habit prompted a study by linguists at the University of Toronto. In 2005, they published a paper asserting that the word "so" was the intensifier used 45 per cent of the time on the show.