The present pater aims to review Barriers framework proposed by chomsky(1986b) to point out some potential problems and to give an alternative definition of barriers.Chomsky assumes that adjunction to non-argument is possible for syntactic movement But this assumption results in overgeneration of ungrammatical sentences.We do not allow any adjunction in syntax,and abandin the Empty Category Princile,instead we propose Head Licensing Cindition and Antecedent Condition.HLC requires empty non-proneminals to be marked by head either lexical or functional and AC states that traces should be 0-subjacent to their antecedents.