consisting of three separate parts or pieces 三件一套的；由三部分组成的 a three-piece suit (= a set of clothes consisting of trousers, a jacket and a waistcoat) 三件式套服（包括裤子、上衣和背心） - (British English)
a three-piece suite (= a set of three pieces of furniture, usually a sofa and two armchairs) 三件一套的家具（通常为一张长沙发和两张单人沙发）
Oxford Collocations DictionaryThree-piece is used with these nouns:- suit
- suite