The office

really good show but the later seasons have too much plot and slowly becomes unfunny. personally i dont like when my sitcoms have plot because its supposed to be "situational" but then they have a story arc that lasts several episodes.

friends may be one of the good examples of sitcom, because its "characters try to do X and Y, hilarity ensues". of course it has some plot but most of the show has the same formula while leading up to the season premieres/finales which are the most plot driven in the series.