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ENG 221 AN INTRODUCTION TO SYNTACTIC MODELS

ENG 221 AN INTRODUCTION TO SYNTACTIC MODELS

3. The baby kicked over the lantern 4. The/baby

The baby/kicked over kicked over/the lantern the/lantern

the baby/kicked over the lantern 5. The baby kicked

baby kicked over the/lantern the/elephant kicked

That is, the native speaker has some kind of intuitive feeling that the baby is a constituent, and that the individual words are constituents, and

that kicked over the lantern is a constituent. He has no such feelings about possible combinations like kicked over the or baby kicked.

The second function of the PSG is to tell us in what basic order the constituents are to be arranged. Native speakers of English will accept

number (6) below, but not any of the other examples:

6. The elephant went stumbling through the orchard.

7. *Stumbling elephant the through the orchard went.

8. *Through stumbling elephant the orchard went 9. *The orchard went through stumbling the elephant

It is customary in Transformational grammar to put an asterisk in front

of sentences that would not be considered grammatical by native speakers.

Having explained the two functions of PSG, it is time to bring in the actual rules:

1. S NP + VP 2. NP (Det) + N 3. VP V + (NP)

This is a partial set of PSG rules for English. The first one tells us that S (sentence) is composed of NP (Noun Phrase), and a VP (Verb Phrase) in

that order. The second rule says that a Noun Phrase – an NP, is

composed of a Noun (N) which may be preceded by a Det (Determiner).

The parenthesis around an element indicates that it is optional. The third rule says that a VP (Verb Phrase) is composed of a V (Verb), which may optionally be followed by an NP (Noun Phrase).

This set of rules will permit all of the sequences in examples (10)-(13), but will not allow any of (14)-(17):

ENG 221 AN INTRODUCTION TO SYNTACTIC MODELS

10. Ngozi screamed 11. The boy left

12. The girl drank a milkshake 13. Some boys saw Elizabeth 14. *Screamed Ngozi

15. *Boy the left

16. *Milkshake a drank girl the 17. *Boys some Elizabeth saw

The acceptable sentences above are made up of words arranged in a particular order. We shall refer to words out of which sentences are composed as its ultimate constituents (they are not further analyzable at

the syntactic level). The order in which the ultimate constituents occur

relative to one another may be described as linear structure of the sentence.

But how does this system assign to sentences the appropriate phrase structure? The answer to this question is given by a convention associated with the operation of ‘rewriting’. We can use the partial phrase structure grammar above to generate the deep structure of some

sentences. To illustrate how the deep structure is generated, we can use a tree diagram. The relationship between the phrase structure rules and a tree diagram is quite strict; a phrase structure rule of the form X Y + Z

matches the tree:

X Y Z

Let us generate the deep structure underlying sentences (10)-(13):

10. Ngozi screamed

S NP VP N V

Ngozi Screamed

ENG 221 AN INTRODUCTION TO SYNTACTIC MODELS

11. The boy left 12. The girl drank a milkshake

S S

NP VP NP VP

Det N V Det N V NP

The boy left Det N

The girl drank a milkshake

13. Some boys saw Elizabeth

S NP VP

Det N V NP

Some boys saw Elizabeth

It is obvious that the phrase markers given above convey the following

information: in (10), the terminal elements Ngozi + screamed is an S which consists of two constituents, NP (Ngozi) and a VP (screamed). In

(11), the terminal elements the + boy + left is an S which consists of NP (the boy) and a VP (left); the NP consists of two constituents, Det (the)

and N (boy). In (12) the terminal elements the + girl + drank + a milkshake is an S which consists of NP (the girl) and a VP (drank a milkshake). The NP to the left of VP consists of two constituents, Det

(the) and N (girl); the VP consists of V (drank) and an NP (a

milkshake), and the NP to the right of VP consists of two constituents, Det (a) and N (milkshake). We can account for (13) in the same way.

We thus see that the phrase structure grammar is much more satisfactory than the finite state grammar. Any set of sentences that can be generated

by a finite state grammar can be generated by a phrase structure

grammar, but the converse does not hold: there are sets of sentences that can be generated by a phrase structure grammar, but not by a finite state

grammar. Phrase structure grammars are intrinsically more powerful than finite state grammars – they can do everything that finite state

grammars can do – and more. Phrase structure grammars contain rules which are capable not only of generating strings of linguistic elements, but also of providing a constituent analysis of strings, and hence more information than finite state grammars.

ENG 221 AN INTRODUCTION TO SYNTACTIC MODELS

SELF ASSESSMENT EXERCISE 2 1. Define ‘phrase structure grammar’

2. State two functions of phrase structure grammars

3. Using the partial PSG rules discussed above, generate the deep structure of the following sentences with the aid of tree diagrams:

(a) The student passed the exam.

(b) Some scholars received their pensions.

(c) Students drive flashy cars.

4.0 CONCLUSION

In this unit, we have tried to present in an outline, what finite state grammars and phrase structure grammars are. Neither the traditionalists

nor the structuralists provided an adequate account of the syntax of natural languages. Although the grammars we have discussed are not

without problems in syntactic analysis, they recognize that language is creative, if not infinite. Therefore, grammars must be generative.

5.0 SUMMARY

You have learnt in this unit:

• what finite grammars are;

• what phrase structure grammars are; and

• how to use tree diagrams to generate deep structures of sentences.

6.0 TUTOR-MARKED ASSIGNMENT 1. What do you understand by a tree diagram?

2. Compare and contrast finite state grammar and phrase structure grammar.

3. Draw the deep structure trees for the following sentences:

(a) The Vice Chancellor attended the party (b) She wept

(c) Most lawyers are Senior Advocates (d) The musician performed

ENG 221 AN INTRODUCTION TO SYNTACTIC MODELS

7.0 REFERENCES/FURTHER READINGS

Allerton, D. J. (1979). Essentials of Grammatical Theory. London:

Routledge and Kegan Paul.

Crane, B. L., Edward Yeager and Ranal L. Whitman. (1981).

An Introduction to Linguistics. Boston: Little Brown and Co.

Culicover, P.W. (1982). Syntax. 2nd Edition. New York: Academic Press.

Lyons, John. (1970). Chomsky. London: Fontana Books.

ENG 221 AN INTRODUCTION TO SYNTACTIC MODELS

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