Assignment
1. (This fragment was started in class 3/5)
Note that case marking, related to verbal argument structure, is present in English only in the pronominal system. Note also that it is semantically anomalous for some nounphrases to serve as subjects of certain verbs in English. Create a Prolog program that models the following fragment of English grammar; it should contain in its lexicon entries for he, she, him, her, it, prefers, sleeps, loves, the, and car.
Intended outputs:
She loves him
He prefers it to her It sleeps
She prefers her to the car He loves the car
(and similar)
Unintended outputs:
*him loves the car
*the car sleeps
*the car prefers him to her
*it loves she
Be principled in your approach, with rules for generating nounphrases, verbphrases, and sentences from the lexicon. You can assume that a) the case distinctions boil down to nominative, nonnominative, or unmarked, that b) each verb has a different valence, and that c) something like agenthood or animacy explains why "the car loves him" is ill formed.
2. Unlike English, German allows for determiners to precede proper nouns. Case marking is evident on the determiner, but not the noun, using the following paradigm:
words meaning "the" (for masculine nouns):
der nominative (subject) case
den accusative (direct object) case dem dative (indirect object) case des genitive (possessive) case
This enhanced marking allows for so-called syntactic scrambling in German when all nounphrases include determiners, such as the following examples and their associated glosses (literal morpheme-by-morpheme translations) and meanings:
der Fritz liebt den Hund the Fritz loves the dog "Fritz loves the dog"
den Hund liebt der Fritz the dog loves the Fritz "Fritz loves the dog"
der Hund liebt den Fritz the dog loves the Fritz "The dog loves Fritz"
den Fritz liebt der Hund the Fritz loves the dog "The dog loves Fritz"
der Fritz gibt dem Hund den Knochen the Fritz gives the dog the bone "Fritz gives the bone to the dog"
dem Hund gibt den Knochen der Fritz the dog gives the bone the Fritz "Fritz gives the bone to the dog"
den Knochen gibt dem Fritz der Hund the bone gives the Fritz the dog
"The dog gives the bone to Fritz"
Notice that in all cases, the subject is marked with a nominative determiner, the direct object with an accusative determiner, and the indirect object with a dative determiner. The ordering of elements can vary, provided all determiners are present, but the verb always shows up in so- called second position (after the first nounphrase). Note that objects of both kinds are always adjacent to verbs in verbphrases.
Assuming all of the above as possible outputs, create a Prolog program which models this fragment of German without generating impossible forms like "der Knochen gibt dem Hund den Fritz" ("the bone gives Fritz to the dog") but which generates all of the other valid orderings. Be principled in your approach (you should start by editing your response program for #1, as this will be very helpful). Assume that Knochen must be inanimate.
3. Note the sentences of German which follow, which were purposefully excluded from the previous fragment:
dem Hund gibt der Fritz den Knochen the dog gives the Fritz the bone "Fritz gives the bone to the dog"
den Knochen gibt der Fritz dem Hund the bone gives the Fritz the dog "Fritz gives the bone to the dog"
What is different about these examples with regard to the verb and its object? Explain, in prose, why this difference is problematic for both a Prolog implementation as well as a general syntax tree containing a verbphrase.