A Grammar of Subordinate Structures in English One cannot help but be impressed by the scope and variety of natural sentence structures. Whereas some might have once thought that a language is learned by memorizing its sentences, it is now clear that this is not possible. All normal humans possess the ability to form entirely new sentences, sentences no one has ever heard, read, or uttered before. This, of course, is the creative aspect of language to which adherents of the generative-transformational school of linguistics have repeatedly called our attention.