Assignment 7, Ling 645/CMSC 723, Fall 1997

Logical form and semantic interpretation

This assignment is due in class November 5.

READING:

   Read Chapter 8, with particular attention to
   sections 8.2 through 8.6. 

   Read Chapter 9, sections 9.1 through 9.4.
   The remainder of the chapter is optional.

TO DO:

7.1  Do Allen, Ch 8, exercise 5.  If you are not a native speaker
     of English, talk to someone who is in order to find out
     what the possible interpretations of these sentences are.
     [20 pts]

7.2  For the sentences in Allen, Ch 8, exercise 6,
     specify the roles for each NP (and explain your
     choice if you think it's not obvious), but you don't need
     to give the logical forms. 
     [20 pts]

7.3  Do Allen, Ch 9, exercise 1.
     [20 pts]

7.4  Go into LISP and load Allen's parser as in the last assignment:

       (load "loadFunction")
       (load "LoadParser")

     This time, however, instead of loading the Chapter 4 grammar/lexicon,
     do

       (LoadSection9-3)

     to load the grammar/lexicon of Allen, Section 9.3.
     Then do the following and make sure you understand why each 
     output looks the way it does:

	(bu-parse '(the))
	(show-answers)

	(bu-parse '(man))
	(show-answers)

	(bu-parse '(the man))
	(show-answers)

	(bu-parse '(cry +ed))
	(show-answers)

	(bu-parse '(the man cry +ed))
	(show-answers)

	(bu-parse '(Jill decide +ed in the house))
	(show-answers)

        (bu-parse '(Jill saw the man in the house))
	(show-answers)

   Do NOT turn in traces of any of the above.  To turn in [30 pts]:

     a.  Give JUST the semantic interpretations of JUST the last
         sentence (Jill saw the man in the house). 

     b.  Explain why (bu-parse '(on the house)) gives back two different
         semantic interpretations for the PP when you do (show-answers), 
         and specifically explain why one of them contains a lambda
         expression and the other does not.

     c.  Give two distinct sentences containing the prepositional phrase 
         "on the house", each sentence corresponding to one of the
         semantic interpretations in part (b).   Turn in the 
         semantic interpretation of each sentence.  (Do NOT
         turn in the semantic interpretations of the sub-constituents.)


OPTIONAL [20 pts]

7.5  Edit Grammars/Chapter9.lisp and modify or extend *grammar9-4*
     so that 

       (bu-parse '(Jill put the dog in the house))
       (show-answers)

     gives you an S with the following semantic interpretation:

        (SEM
          (PUTS1 V1312 
             (NAME V1310 JILL) 
             (UNSCOPED THE V1318 (DOG1 V1318))
             (TO-LOC (UNSCOPED THE V1324 (HOUSE1 V1324)))))

     The variables can have different numbers, of course!

     Note that whenever you make changes in the file,
     you'll have to call (LoadSection9-3) to re-load the
     grammar so you can test those changes.  

     Hint for speedier debugging:  you may want to temporarily
     comment out grammar rule -13 in *grammar9-7*, so that you 
     don't have to keep wading through output that contains the
     PP attached to the NP ("dog in the house").

     For full (extra) credit, the above must be the ONLY
     semantic interpretation returned for the full sentence.
     (Partial credit will be given if there are multiple 
     sentential interpretations.)

     TURN IN:

       a. The output of (show-answers) after you've run bu-parse.
          Do NOT turn in a dribble containing the output generated
          during bu-parse.  (That is, turn in everything below
          "THE BEST PARSES FOUND".)

       b. A printout of your modified *grammar9-4*.
          (Do NOT turn in the whole Chapter9.lisp file!)