The name Transformational Generative Grammar suggests that there are two aspects of the theory. The grammar it provides is both ‘trans-formational and generative. These two aspects are not logically dependent upon each other, though the theory gains Reliability from the interaction between the two. Hence it is necessary to understand these two terms.
It is because of the shortcomings of phrase structure grammar and because of other reasons that Noam Chomsky came to the view that ‘notions of phrase structure are quite adequate for a small part of the language and it can be derived by repeated application or rather simple set of transformations to the strings , given by the phrase structure grammar to cover the entire language directly.
We would lose the simplicity of the limited phrase structure grammar and of the transformational development.’
Simply speaking a transformation can he thought of as transforming one sentence into another, the deep structure into surface structure. Whereas active sentences are ‘kernel’ sentences, passives are the transforms. There are however plenty” of other transformations.
R.H. Robins says: “Essentially, Transformation is a modern grammatical concept developed by Chomsky school of thought in linguistics. It states how the deep and surface structures of many sentences in languages can be generated or transformed formally as the result of specific transformations communication to in basic type of sentence structures”.
For example has John seen Mary? Is a transform of John has seen Mary (by simple transfer of “has” which is technically described as ‘permutation’: A snake was killed by Ali is the transform ‘of the sentence in the active voice: Ali killed a snake (by passivization). Similarly the man who was standing there ran away is the transformation of the two sentences.
The man ran away
And The man standing there.
The second characteristic of Transformational generative grammar is “Generative” it is also called dependency and relational grammar.
Why Linguist love Transformatinal Generative Grammar?
This means that a grammar must generate deep and surface level of grammatical sentences of a language. It predicts the universal notion that all the human being possesses common basic knowledge of grammar in their brain.
By this is not meant that a grammar should literally (at any time) bring all these sentences into existence. It means merely that “grammar must be so formulated that by following its rules and conventions we could produce all or any of the possible sentences of the language. To ‘generate’ is thus to ‘predict’ what could be sentences of the language or to ‘specify’ precisely what are the possible Sentences of the language. Thus grammar should ‘generate’, ‘specify’, ‘predict’ the grammatical/acceptable sentences of the language and not the ungrammatical/ unacceptable ones.
So a generative’ grammar is not concerned with any actual set of sentences of the language but with possible set of sentences. We are not concerned merely solely even primarily with any observed sentences (utterances) that have come in to mind, but rather with those that can, or could have come in to mind. The advocates of TG have said that any corpus consists of finite number of sentences. This notion infinity is a result of what is known as “recursion concept” that states, we can attempt again and again the same linguistic device in more reliable way.
Secondly, a grammar is generative is to say that is explicit that is it explicitly, clearly, methodically, accurately indicates just what are the possible sentences of the language. It leaves nothing to chance nothing to the reader’s intelligence or his knowledge of the language or the way in which languages usually work/It should leave nothing to the imagination and should be formulated step by step in such a way that the generation of the sentences of a language should be a pure mechanical procedure given a person who did not know the language could generate sentence by following the step by rules
The explicitness and the predictive nature of such a grammar can be summed up in one word the word generation should not automatically lead to conclude that all generative grammars are transformational. Any type of grammar which is explicit and predictive is generative. But not all generative grammars are transformational.