LING 388: Language and Computers

Sandiway FongLecture 21

g20.pl

• From the course website, g20.pl incorporates:– perfective have, progressive be and passive be

perfectivehave progressive

be

passivebe

main verb

Start

g20.pl

• S rules:

g20.pl

• VP rules:

g20.pl

• Auxiliary verb rules:

g20.pl

• NP rules:

g20.pl

• Lexical rules for determiners and nouns:

g20.pl

• Lexical rules for main verbs:

g20.pl

• SBAR rules:

• Subject verb agreement table:

Case Constraint

there is a Case Constraint on pronouns• Examples

1. I ate the sandwich (active with subject pronoun)2. *me ate the sandwich3. the boy saw me (active with object pronoun)4. *the boy saw I5. the sandwich was eaten (passive)6. *the sandwich was ate7. the sandwich was eaten by me (passive + subject in by-

phrase)8. *the sandwich was eaten by I

Case Constraint

• We need to add a lexical feature Case to all NPs, currently NPs report Parse, Person and Number:

Since common and proper nouns can appear in any position, we leave Case unrestricted, i.e. set the value of Case to be the anonymous variable (_) for those NPs

Case Constraint

• We need to add lexical entries for pronouns to report the value of Person, Number and Case

http://uptodate-amef.blogspot.com/2011/09/personal-pronouns.html

Values:nom Nominativeacc Accusative

Case Constraint

• NPs are inserted as subject and object of clauses (also objects of prepositions)

Values:nom Nominativeacc Accusative

Values:nom Nominative

Subject positionsacc Accusative

Object positions

nom

Case Constraint

• NPs are inserted as subject and object of clauses (also objects of prepositions)

Values:nom Nominative

Subject positionsacc Accusative

Object positions

acc

PP by-Phrase

• Example:– The sandwich had been eaten by me/him/*I/*he– Parse?

• Only one by-phrase (agent) is allowed• It attaches to the vbn (-en) verb following

passive be in the Stanford Parser

acc

PP by-Phrase

• Modify the vp_passive rule associated with passive be:

• Desired output: