Semi-detached housing consists of pairs of houses built side by side as units sharing a party wall and usually in such a way that each house's layout is a mirror image of its twin. this style is sometimes colloquially called a duplex; elsewhere, however, "duplex" refers to a building split into two flats/apartments (one above the other). The style is usually referred to in the mid-Atlantic (particularly Philadelphia) as a twin. ' z3 e. m% V: m; J. V' D2 z( c4 H# y4 H ( k" O$ j) b3 n& s$ e8 f就是一个房子俩家了。应该和RF2差不多吧