foursome

n 1 four people joining together to play a game, esp golf 四人参加的游戏（尤指高尔夫球）. 2 two couples undertaking a leisure activity together 两对男女一同参加的娱乐活动: Let's make (up) a foursome and go out to a restaurant. 咱们四个人（两对男女）一起下饭馆吧.

foundation-stone, foundations, founder, founder-member, founding father, foundling, foundry, fount, fountain, fountain-head, fountain-pen, four, four-, four-in-hand, four-letter word, four-ply, four-poster, four-square, four-wheel drive, fourfold, fourteen, fourteenth, fourth, fowl, fowl pest, fox, fox-hunting, fox-terrier, foxglove, foxhole, foxhound, foxtrot, foxy, foyer, FPA, Fr, fracas, fraction, fractional, fractionally,