There are two kinds of adjectives. Strong and soft. The strong ones VELKÝ, MALÝ, ČERNÝ have masculine, feminine and neuter forms. The soft ones JARNÍ, ZVLÁŠTNÍ, KUŘECÍ have only one form. If an adjective ends in I, it is soft. The Y or I are more or less given by grammar. C is always followed by i, so is ň (and it may not look like it but Jarní and zvláštní both have a hidden ň there).
So with soft adjectives you have ZVLÁŠTNÍ MUŽ, ZVLÁŠTNÍ ŽENA, ZVLÁŠTNÍ DÍTĚ, ZVLÁŠTNÍ MĚSTO.