Muhammad said: "Ghawran" is an infinitive used as an adjective; you say: "ma'un ghawrun" (sunken water), "ma'ani ghawrun" (two sunken waters), and "miyahun ghawrun" (sunken waters), just as you say: "hadha 'adlun" (this is a just person), "hadhani 'adlun" (these two are just persons), and "ha'ula'i 'adlun" (these are just persons).