[…] minimal sintactically functioning units ("formatives") […]. - Chomsky (1969), a pag.3
[…] we can say that a formative must be regarded as a pair of sets of features, one member consisting of the "inherent" features of the lexical entry or the sentence position, the other member consisting of the "noninherent" features introduced by transformation. - Chomsky (1969), a pag.182