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costume d'affaires and costume d’affaires.
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bien habillé personne, costume, costume pantalon, tailleur-pantalon, pantalon costume, pantsuit, personne bien habillé, and pantalon de costume.
This prank is absolutely hilarious. Replace the mirror in a restroom with a window pane, place a set of identical twins in identical rooms opposite each other and proceed to prank everyone who walks in. :D