1. November 9, 2004 1 Lexicon (An Interacting Subsystem in UG) Part-I Rajat Kumar Mohanty Email: rkm@cse.iitb.ac.in rkm@cse.iitb.ac.in IIT Bombay

2. November 9, 2004 2 Levels of Representation in Universal Grammar (UG) Lexicon Move -alpha D-Structure S-Structure LF (logical form) PF (phonetic form)

3. November 9, 2004 3 The Theory of UG Two conditions Two conditions Compatible with the diversity of existing grammars Compatible with the diversity of existing grammars Sufficiently constrained and restricted Sufficiently constrained and restricted Central Concept Central Concept grammar not language. grammar not language. Language: derivative at a higher level of abstraction from actual neural mechanism. Language: derivative at a higher level of abstraction from actual neural mechanism.

4. November 9, 2004 4 Interacting subsystems UG consists of interacting subsystems UG consists of interacting subsystems Various subcomponents of the rule system of grammar Various subcomponents of the rule system of grammar Subsystems of Principles Subsystems of Principles

5. November 9, 2004 5 Subcomponents Subcomponents of the rule system Subcomponents of the rule system Lexicon Lexicon Syntax Syntax Categorial component Categorial component Transformational component Transformational component PF-component PF-component LF-component LF-component

6. November 9, 2004 6 Principles Subsystem of Principles Subsystem of Principles X-bar Theory X-bar Theory Bounding Theory Bounding Theory Government Theory Government Theory Theta-theory Theta-theory Binding Theory Binding Theory Case Theory Case Theory Control Theory Control Theory

7. November 9, 2004 7 Lexicon Overgeneration Overgeneration Subcategorization Restriction Subcategorization Restriction Selectional Restriction Selectional Restriction Separating the Lexicon from Syntax Separating the Lexicon from Syntax Lexical Derivation Lexical Derivation

8. November 9, 2004 8 Overgeneration Ungrammaticality Ungrammaticality The boy relied on the girl. The boy relied on the girl. * The boy relied the girl. * The boy relied the girl. *The boy relied. *The boy relied. Grammatically Sound but Semantically Odd Grammatically Sound but Semantically Odd *The boy frightens sincerity. *The boy frightens sincerity. *Sincerity kicked the boy. *Sincerity kicked the boy.

9. November 9, 2004 9 Overgeneration PS Rules for the given sentences PS Rules for the given sentences S  NP VP VP  V (NP) (PP) NP  Det N V  rely Det  the N  boy, girl

10. November 9, 2004 10 Subcategorization Restrictions Subcategorization Frames Subcategorization Frames Subcategorization Rules Subcategorization Rules

11. November 9, 2004 11 Subcategorization Frames Specify the categorial class of the lexical item Specify the categorial class of the lexical item Specify the environment Specify the environment Examples Examples kick: [V; _ NP] kick: [V; _ NP] cry: [V; _ ] cry: [V; _ ] rely: [V; _PP] rely: [V; _PP] put: [V; _ NP PP] put: [V; _ NP PP] think: : [V; _ S` ] think: : [V; _ S` ]

12. November 9, 2004 12 Subcategorization Frames The information in the subcategorization frame implies that kick can only be inserted under a V node in a VP structure in which V has an NP sister. The information in the subcategorization frame implies that kick can only be inserted under a V node in a VP structure in which V has an NP sister. The subcategorization information is associated with the individual lexical items in their lexical entries. The subcategorization information is associated with the individual lexical items in their lexical entries.

13. November 9, 2004 13 Subcategorization Rules These rules make a specific lexical item sensitive to the subcategorization properties of the lexical item. These rules make a specific lexical item sensitive to the subcategorization properties of the lexical item. Selection of a frame depends on the subcategorization properties of the verb. Selection of a frame depends on the subcategorization properties of the verb. V y / { _NP] _ ] _PP] _NP PP] _S`] Subcategorization Rule: }

14. November 9, 2004 14 Subcategorization Rules The boy relied on the girl The boy relied on the girl 1. S  NP VP 2. VP  V (NP) (PP) (S`)… 3. NP  Det N 4. V  rely / _PP] 5. P  on / _NP] 6. Det  the 7. N  boy, girl

15. November 9, 2004 15 Context Free and Context Sensitive Rules Rule (4) ensures the non-generation of Rule (4) ensures the non-generation of *The boy relied. *The boy relied. *The boy relied the girl. *The boy relied the girl. Rule (4) and (5) are context sensitive rules Rule (4) and (5) are context sensitive rules Rule (1-3) are context free rules Rule (1-3) are context free rules

16. November 9, 2004 16 Selectional Restrictions Necessity of a Mechanism Necessity of a Mechanism Can we exclude these two ill-formed structures ? Can we exclude these two ill-formed structures ? *The boy frightened sincerity. *The boy frightened sincerity. *Sincerity kicked the boy. *Sincerity kicked the boy. A system should include a mechanism which ensures that only nouns with appropriate properties are associated with given verbs in a given context A system should include a mechanism which ensures that only nouns with appropriate properties are associated with given verbs in a given context

17. November 9, 2004 17 Selectional Restrictions Inherent Properties of Nouns Inherent Properties of Nouns [+/- ABSTRACT], [+/- ANIMATE] [+/- ABSTRACT], [+/- ANIMATE] Like subcategorization properties, they are specified in the lexical entries Like subcategorization properties, they are specified in the lexical entries Sincerity [+ ABSTRACT] Sincerity [+ ABSTRACT] Boy [+ANIMATE] Boy [+ANIMATE] Lexical information of this type can be used to set up a context sensitive ‘rewrite rule’ Lexical information of this type can be used to set up a context sensitive ‘rewrite rule’

18. November 9, 2004 18 Selectional Restrictions Selectional Rules Selectional Rules A selectional rule specifies certain selectional restrictions associated with a verb (presumably other categories: N, A, P) A selectional rule specifies certain selectional restrictions associated with a verb (presumably other categories: N, A, P) V y / {} [+/-ABSTARCT] [+/-ANIMATE] V frighten / [+/-ABSTARCT] [+ANIMATE] {} __

19. November 9, 2004 19 Exercises Workout the subcategorization frame of each of the lexical items: aspire, declare, conduct, aware, transport, arrange, deliver, silent Workout the subcategorization frame of each of the lexical items: aspire, declare, conduct, aware, transport, arrange, deliver, silent Write selectional rules for the following verbs: cry, rely, put, think, abandon, aspire Write selectional rules for the following verbs: cry, rely, put, think, abandon, aspire

20. November 9, 2004 20 Exercises Consider the following examples Consider the following examples John believes that Mary left early. John believes that Mary left early. *John believes if Mary left early. *John believes if Mary left early. *John wonders that Mary left early. *John wonders that Mary left early. John wonders if Mary left early. John wonders if Mary left early. Suggest a formal way of encoding the property of the verbs believe and wonder. Suggest a formal way of encoding the property of the verbs believe and wonder. Tips: Tips: Workout the subcategorization frame Workout the subcategorization frame Write the subcategorization rules Write the subcategorization rules Assign selectional restrictions Assign selectional restrictions

21. November 9, 2004 21 Sources and further reading Comsky, Noam. 1965. Aspects of the Theory of Syntax. CUP, Cambridge. Comsky, Noam. 1965. Aspects of the Theory of Syntax. CUP, Cambridge. Comsky, Noam. 1981. Lectures on Government and Binding. Foris, Dordrecht. Comsky, Noam. 1981. Lectures on Government and Binding. Foris, Dordrecht. Ouhalla, Jamal. 1994. Introducing Transformational grammar. Arnold, London. Ouhalla, Jamal. 1994. Introducing Transformational grammar. Arnold, London.

22. November 9, 2004 22 THANK YOU