Anonymous  +  515537 Mon, 19 May 08 11:37 AM Sometimes words that are usually used as nouns are used as adjectives. Ex : The shoe store also sells books When a noun is used as an adjective, it is singular in form, NOT plural. But I found some english documents that contains some identical structure like : sales assistant, clients need. In this case, why are "sales" and "clients"  plural in form ? When will they be plural in form ? Anonymous Plurals, Nouns

	Mister Micawber  +  515579 Mon, 19 May 08 12:56 PM . There is no absolute rule, but most are, as you say, in the singular (a shoe store, a five-minute break), while some are plural (systems engineer, cattle ranch).  In your examples, sales assistant perhaps because the assistant's job is sales; sales is his job-- it is a department name.  Clients need sounds odd to me; can you supply an authentic example? Mister Micawber Joined on Wed, Aug 4 2004 Yokohama Veteran Member 30,825 'The question is,' said Humpty Dumpty, 'which is to be master-- that's all.' Plurals, Nouns