\textbf{16.} The concept of ``an'' in which words, respectively, means: \textbf{sign of plural, active participle, relative, adjective of time}?
(1) Ravandegan, sokhanserayan, Gilan, Khazan \hfill (2) Mardan, Kiyan, Sepandan, Sepidedaman
(3) Sokhangoyan, Gorgan, Kohan, Bamdadan \hfill (4) Niakan, Kharaman, Babkan, Nobaharan
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