About "Siheyuan", a courtyard residence, which of the following choices are right?

A、"Siheyuan"isknownathomeandabroadasmainoldPekinesehabitancyforgenerations.
B、"Siheyuan"consistsofthenorthhouse,southhouse,eastandwestwinghouses,eastandwestcornerhouses.
C、Theprincipalroomisbuiltonthesouth-northaxis,andtwowingroomsarelocatedonbothsidesofit.
D、Thefamilyeldersusuallyliveinthewingrooms.