linguistic:voice_change, structural:summarization
Etymology

Trade is from Middle English trade ("path, course of conduct"), introduced into English by Hanseatic merchants, from Middle Low German trade ("track, course"), from Old Saxon trada ("spoor, track"), from Proto-Germanic *tradō ("track, way"), and cognate with Old English tredan ("to tread").

Commerce is derived from the Latin commercium, from cum "together" and merx, "merchandise."