(London Weekend TV sitcom,1977-86)

Feeble (and in this century offensive) comedy about a language class attended by people of many nationalities.

Episode 2.5: Don't Forget the Driver
This episode, in which the class takes a coach trip, is worth catching, however. The first coach seen is imposing VUR227K, an AEC Reliance/Van Hool with Best Tours of London:

…but the bus actually used for the trip is grubby Guy Vixen/Eastern Coachworks MXX310, which was new to London Transport Country Area as GS10 in 1953. It's seen here still in London Country livery with the fictional fleetname 'Smoothride Tours':