The transformational grammar was a theory of how grammatical knowledge is represented and processed in the brain. Developed by Noam Chomsky in the1960's, the transformational grammar consisted of:
1. Two levels of representation of the structure of sentences:
· an underlying, more abstract form, termed 'deep structure', and
· the actual form of the sentence produced, called 'surface structure'.
The DEEP STRUCTURE is represented in the form of a hierarchical tree diagram, illustrating the abstract grammatical relationships between the words and phrases within a sentence.
2. A system of formal rules specifying how deep structures are to be transformed into surface structures.
Consider the two sentences:
a) "Steven wrote a book on language" and
b) "A book on language was written by Steven."
Chomsky held that there is a deeper grammatical structure from which both these sentences are derived. The transformational grammar provides a characterization of this common form and how it is manipulated to produce actual sentences.
Take the sentence "Who will John see." This corresponds to its surface structure. According to the transformational grammar, we form this sentence by unconsciously applying transformation rules to the underlying deep structure given in the phrase structure tree of the form "John will see who." In this particular case, the transformation rule applied is termed "Wh-movement."
The transformational grammar formed the basis for many succeeding theories of human grammatical knowledge. Since Chomsky's original presentation, many different theories have emerged. Although current theories differ significantly from the original, the notion of a transformation remains a central element in most models.
One of Chomsky's most influential and controversial views is that all human languages have a structure in common called universal grammar. A number of different lines of evidence help support this view. All normal speakers of a language have extensive knowledge of its grammatical structure (or syntax).
For example, any speaker of English knows that 'He loves her' is grammatical, while 'Him loves she' is not. This knowledge of syntax can be quite simple. The results of removing the word 'that' from the sentence 'the dog that I saw has rabies' is a new sentence that is still well formed. But 'that' cannot be removed from the sentence 'the dog that bit me has rabies'. Although most of us are unable to explain the rule that governs when 'that' may be safely deleted from a sentence, we are all able to recognize which sentences are correct and which sentences are not correct. This ability to distinguish well formed from ill formed sentences is called our linguistic competence.
Competence - Performance Distinction
Linguistic competence is not always reflected in actual speech. Our linguistic performance is peppered with 'ums' and 'ahs', false starts and sentence fragments. Nevertheless, when asked, we are still able to judge the difference between those utterances that live up to the rules of English and those that do not. Although we are probably not consciously aware of any of these rules, our unconscious mastery of them is revealed in our linguistic competence.