EMPTY CATEGORIES IN TRANSFORMATIONAL RULES

There are three theories that are always developed in any study of language, namely theory of language structure, theory of language acquisition, and theory of language use. Among those three theories, theory of language structure is regarded as the most important one. It is assumed that if someone knows the structure of language, he/she can develop theories about how language is acquired and used. It makes Chomsky interested in developing the theory of language structure. Chomsky introduced a theory of grammar called Transformational Generative Grammar or Transformational Syntax. Transformational Syntax is a method of sentence fomation which applies some syntactic rules (or also called transformational rules). Transformational rules consist of three types, namely movement transformation, deletion transformation, and substitution transformation. When those transformational rules are applied in a sentence, they will leave empty categories. Empty categories can be in the form of Complementizer (Comp), Trace, and PRO. The objectives of this article are to elaborate those empty categories; to show their appearance in the transformational rules; and to describe the characteristics of each empty category. Comp, Trace, and PRO can be found in movement and deletion transformation. In this article, tree diagram and bracketing are used as the methods of sentence analysis.


INTRODUCTION
states that there are three inter-related theories which any detailed study of language ultimately seeks to develop, From the theories above, the theory of language structure is the most important one. The reason is that if someone knows the structure of language, he/she can develop theories about how it is acquired and used. Therefore, most of Chomsky's works have been devoted to the attempt to develop a Theory of Language Structure.
Theory of Language Structure can be developed in two steps. The first step is to formulate detailed descriptions (known technically as grammars) of particular languages for example English, French, etc. This is known as the study of Particular Grammar. A grammar of particular language will take the familiar form of a set of rules or principles which tell us how to speak and understand the language. More precisely, a grammar will comprise a set of rules or principles which specify how to form, pronounce, and interpret phrases and sentences in the language concerned. The second 68 step is to abstract from particular grammars common. This is known as the study of Universal Grammar (Radford, 1988).
Chomsky introduced a theory of grammar called Transformational Generative Grammar (TGG) or Transformational Syntax. TGG or Transformational Syntax is a method of sentence formation. In sentence formation, a sentence derives from Deep Structure (DS) which exixts in the mind of speakers. Deep Structure will show the meaning intended by the speakers. Syntactic rules will be applied in the Deep Structure; then, Surface Structure (SS) will be obtained. Deep Structure can be defined as the structure of a sentence which is represented in the tree diagram and phrase markers which becomes the input of the application of (a) syntactic rule(s), which underlies the meaning of the sentence; meanwhile, Surface Structure is the structure which is obtained from the application of (a) syntactic rule(s) to the deep structure of a sentence, which is generally used in communication.
The syntactic rules (transformational rules) are applied to the Deep Structure and produce, as their output, the surface structure. In other words, the Deep Structure accounts for the meaning of the sentence; meanwhile, the surface structure accounts for the form of the sentence (Lester, 1971). Ouhalla (1999) prefers to say that Deep Structure as the underlying representation and Surface Structure as the derived representation.
Schematically, the relation between Deep Structure and Surface Structure can be seen in the following. In deletion transformation, the constituents are not moved, but deleted. The reason for this deletion is that the two similar lexical categories (words) have similar position. So, it is not necessary to mention the word twice. Therefore, one of the words must be deleted. One example of deletion transformation is the deletion of coreferential VP or gapping that can be seen in the following.
Andre likes tea and Tony coffee. The changing Deep Structure into Surface Structure by applying transfromational rules will leave empty categories. The empty categories can be in the form of Complementizer (Comp), Trace, and PRO. In the next session, those empty categories will be elaborated along with their characteristics.

DISCUSSION
Empty category is an important theory in Generative Syntax. It was introduced first by Chomsky in his book 'Aspects of the Theory of Syntax' in 1965. In his first book 'Syntactic Structures', Chomsky did not mention this theory, but he found this theory later and he discussed it in his next books as Jumino (2004) says: In the first phase of the theory of Generative Linguistics (henceforth GL) which was marked by the publication of the legendary monograph Syntactic Structures in 1957, Chomsky as the pioneer had not proposed the so-called empty category………In further development of the theory in the publication of Aspects of the Theory of Syntax in 1965, Chomsky made some revisions to the theory posited earlier, and thus known as a Standard Theory. At this phase empty category was introduced in the form of a dummy node symbolized as ∆. In 1975, Chomsky introduced the Trace Theory of Movement Rules in the publication of Reflection on Language. (p. 93-94) In the theory of Generative Linguistics, empty category consists of three types. They are Complementizer (Comp), Trace, and PRO.

Comp
According to Jumino (2004), Complementizer is derived from its name in which the complement of a transitive verb in the form of a clause generally begins with a subordinator. He also adds that in the phrase markers, the subordinator cannot be treated properly without an additional  Instead of the complementizer 'that', Comp may also be occupied by other lexical categories such as wh-words as in (2.a).

Trace
Trace is an empty category which is considered the most significant one in the theory of Generative Linguistics. It is the result of a movement transformation as postulated in the following rule called Trace Convention (Ouhalla, 1999,p.66). The rule says:

Movement transformations leave a trace behind
For a clear description, let us see the example below.

PRO
PRO known as a big PRO is an empty category which typically occurs in the subject position of non-finite clauses. For example: In the tree diagram, the sentence (9.a) can be analyzed as follows: PRO may be identified from its features (Jumino, 2004). The first feature is that PRO is the result of a deletion transformation as can be seen in (9.a). In (9.a), the deletion transformation is called Coreferential NP Deletion (CNPD). However, a constituent is also deleted if it is unspecified The subject NP in the non-finite embedded clause 'someone' is unspecified, so it can be deleted.
The second feature of PRO is that it is ungoverned as adopted from Ouhalla (1999:247) and Haegeman (1994:272) called PRO Theorem which says that:

PRO must be ungoverned
For example, let see the example of sentence (10) above in which the subject of the lower clause 'someone' is not governed by any category so that PRO in (10) is ungoverned. However, see another example below.
(11) It is difficult for someone to predict the future.

*It is difficult [IP for [IP PRO to predict the future]]
The sentence (11) is excluded as PRO in this respect is governed by the preposition 'for', thus violating PRO Theorem.
The third feature of PRO is that it may or may not have an antecedent. For example, PRO in (9.a) has the same index as the subject of the matrix clause 'Santo' which constitutes its antecedent and this kind of PRO is called a controlled PRO, and the antecedent is the controller.
However, PRO may sometimes have no antecedent as in (10) (13) is anaphoric as it is dependent on another NP for its interpretation i.e. 'Jim' which can be observed from the index.
PRO is significant to account for not only infinitive clauses as given earlier but also other types of non-finite clauses in various distributions (Jumino, 2004:109). The case of gerund clause may also support the evidence of PRO Theorem as (14).
(14) Bill hates sitting on the front row.

CONCLUSION
Sentence is derived from Deep Structure (DS) which exists in the mind of speakers. Deep Structure shows the meaning intended by the speakers. Syntactic rules will be applied in the Deep Structure; then, Surface Structure (SS) will be obtained. Deep Structure can be defined as the structure of a sentence which is represented in the tree diagram and phrase markers which becomes the input of the application of (a) syntactic rule(s), which underlies the meaning of the sentence; meanwhile, Surface Structure is the structure which is obtained from the application of (a) syntactic rule(s) to the deep structure of a sentence, which is generally used in communication.