examples of armchairs 
Sofa with an irregular back joining two arms of different heights.
Upholstered quilted sofa whose arms are the same height as its back.
Long lounge chair on which one can recline, equipped with an upholstered headrest and back, the latter extending only a part of the length of the chair.
Sofa that seats two people.
Long upholstered armchair that seats several people.