Linguistics 567: Grammar Engineering

Lab 7 Due 5/20

Background

The goal of this lab is to be able to parse the two sentences I can eat glass. It doesn't hurt me., assign them appropriate semantics, and generate back. You have already done some of the work: from previous labs, your grammar should already handle pronouns, case (if applicable), and transitive verbs. You should already have most of the vocabulary required (except can and not). You may need to add the appropriate verb forms, and may get inspired to add some lexical rules for verbal agreement in the process (if applicable, and if you haven't already).

You will need to add a treatment of however your language expresses the modal meaning can and of sentential negation. The instructions below outline several possibilities. If none of them fit what's going on in your language, talk to me :).

Semantic representations

Your semantic representations for the two sentences should look approximately like this, modulo the relations showing up in a different order, the variables (e's, x's, and h's) showing up with different numbers, the SEMSORT information showing up in different places.

I can eat glass.
```
< h1,u2:SEMSORT,
{h3:pronoun_n_rel(x4:SEMSORT:FIRST:SG),
h5:pronoun_q_rel(x4, h7, h6),
h8:_can_v_rel(e9:SEMSORT:TENSE:ASPECT:MOOD, h10),
h10:_eat_v_rel(e11:SEMSORT:TENSE:ASPECT:MOOD, x4, x12:SEMSORT:THIRD:SG)
h13:_glass_n_rel(x12),
h14:indef_q_rel(x12,h16,h15)}
{h6 qeq h3,
h15 qeq h13} >
```
Things to note about this representation: _can_v_rel is a one-place relation (i.e., we're treating can as a raising verb, for now), taking the handle of the _eat_v_rel as its argument. The _eat_v_rel is a two-place relation taking x4 (the index from the first-person pronoun) and x12 (the ARG0 of _glass_n_rel) as its arguments.
It doesn't hurt me.
```
< h1,u2:SEMSORT,
{h3:pronoun_n_rel(x4:SEMSORT:THIRD:SG),
h5:pronoun_q_rel(x4, h7, h6),
h8:_neg_r_rel(u10:SEMSORT, h9),
h11:_hurt_v_rel(e12:SEMSORT:TENSE:ASPECT:MOOD, x4, x13:SEMSORT:FIRST:SG),
h14:pronoun_n_rel(x13),
h15:pronoun_q_rel(x13, h17, h16)},
{h6 qeq h3,
h9 qeq h11,
h16 qeq h14} >
```
Things to note about this representation: The _neg_r_rel takes a handle as its argument, which is related through a qeq to the handle of the _hurt_v_rel. The qeq quantifiers to scope above or below _neg_r_rel so that I can't eat some cheese can either mean 'There is some cheese that I can't eat', or 'I can't eat just some cheese (I end up eating more)'. (The relationship between the _can_v_rel and the _eat_v_rel above should similarly be mediated by a qeq. However, the way the Matrix is written, this will only happen if we fix things so that there's a message relation for the embedded clause. We'll just live with the inaccuracy for now.)

can as an auxiliary verb

Use this version if in your language the morpheme expressing the same notion as can is a separate word which takes a VP complement and a subject.

Define a new verb type which inherits from your verb-lex and trans-first-arg-raising-lex-item (and take a look at the definition of this type in matrix.tdl so you know what they're doing).
- In addition to inheriting from these types, your new type should put appropriate constraints on the values of ARG-ST and the valence features.
- Make sure that it constrains the part of speech of each argument.
Define a lexical entry (with PRED value '_can_v_rel which inherits from your new type.
Create the appropriate form of the verb meaning eat, either directly as a lexical entry, or via a lexical rule.
Ensure that only that form of eat can appear as the complement of can (and add whatever items you use to test this to your master testsuite), and that the new form of eat can or can't appear in matrix clauses (as appropriate).
- In English, this involves defining a feature FORM on verb (subtype of head), somewhat similar to CASE on noun.
Parse your translation of I can eat glass, and examine the chart for extra edges. Are they legitimate, or spurious? If they're spurious, try to rule them out (and then rerun your master testsuite to see if they were, in fact, spurious :-).
Parse your translation of I can eat glass and see if you get the right semantics. Debug as necessary.

can as a bound morpheme

Use this version if the morpheme expressing the same meaning as can in your language attaches morphologically to the main verb of the sentence.

The first step is to decide which lexical rule type is appropriate. Look at the section of matrix.tdl titled "Lexical Rules" and see if any of the xxx-only-xxx-rule types are appropriate. If not, construct an appropriate one out of the next level of supertypes. I suspect that infl-cont-change-only-ltol-rule will be a likely candidate, unless you have concomittant changes to the valence features (such as the CASE value required on one of the arguments).

infl-ltow-rule won't be appropriate, because it assumes that no relations are added via C-CONT. If this rule is a true lexeme-to-word rule (takes a stem from [INFLECTED -] to [INFLECTED +]) you'll want to add a type like the following:

    infl-add-ccont-ltow-rule := same-non-local-lex-rule &
                                same-cat-lex-rule &
                                same-ctxt-lex-rule &
                                same-agr-lex-rule &
    [ INFLECTED +,
      DTR.INFLECTED - ].

Your subtype for this particular rule will now need to constrain the MSG and HOOK of the mother (MSG should be the same as the daughter, probably also the HOOK.XARG), as well as the C-CONT (see below).

Regardless of the type you choose for your lexical rule, the subtype will need to add the following constraints:

The lexical rule's C-CONT.HCONS is empty (< ! ! >).
The lexical rule's C-CONT.RELS contains a single relation of type arg1-ev-relation. The PRED value of that relation should be '_can_v_rel, the LBL should be identified with the C-CONT.HOOK.LTOP, the ARG0 with the C-CONT.HOOK.INDEX and the ARG1 should be identified with the daughter's LTOP.

Add an instance for your lexical rule to irules.tdl, with the appropriate spelling change information.

Constrain your lexical rule to apply only to verbs, and test this. Add the sentences you used to test it to your master testsuite file.

If you have other verbal inflection in your language, determine which lexical rule has to go first, and constrain the rules to only apply in that order. Make up nonsense forms with the affixes attached the other way around, and make sure that they don't parse. Add these sentences to your master testsuite file. If your other affixes attach to the other end of the verb, you'll want to constrain the order anyway, or you will end up getting double parses.

Parse your translation of I can eat glass and see if you get the right semantics. Debug as necessary.

Negation as an adverb modifier

Use this version if your language expresses sentential negation via an adverb which modifies the V, VP or S.

(Note: English has two forms of sentential negation "contracted", which is actually an affix on the verb, cf. Zwicky and Pullum 1983, and the full-form adverb. This adverb is not actually treated syntactically as a modifier in sentential negation, but rather selected by auxiliary verbs, including the do of do-support. For the details of this analysis, see Sag, Wasow and Bender 2003 chapter 13 and Kim and Sag 1995. I would be surprised if another language being treated in this class had a system very similar to the English one, as it seems like a pretty quirky part of English grammar. Further, it's a subtle matter to establish what is actually going on in English, and I don't think anyone would have time in one week to show the same about another language.)

Determine where your negative adverb attaches: to V, VP or S and whether it attaches to the left or to the right of the node it attaches to.
For testing purposes, develop a set of sentences contrasting the correct attachment with the incorrect attachments.
Negative adverbs are scopal modifiers, so even though we did adverbs in the previous lab, you'll need to add some machinery:
- Define an instance of adj-head-scop-phrase and/or head-adj-scop-phrase in rules.tdl. (These types are fairly fully specified, which means you'll most likely not need to put anything in esperanto.tdl.) Which one you pick depends on whether your negative adverb is prehead or posthead (or either). Look at the type definitions in matrix.tdl to decide which is appropriate.
- Create a subtype of basic-scopal-adverb-lex. That type (through its supertypes) does much of the work for you. You will need to constrain is VAL and MOD..CAT values. The matrix type also leaves ARG-ST underconstrained. For consistency, if your adverb takes no arguments (and I'd be a bit surprised if the negative element did), ARG-ST should be constrained to be empty as well.
- Create a lexical entry which inherits from scopal-adverb-lex and introduces a relation with the PRED value 'neg_r_rel.
Test your grammar. Does the adverb show up only where it's supposed to? Do you get the right semantics for It doesn't hurt me.? Debug as necessary.

Negation as a verbal affix

Use this version if your language expresses sentential negation by adding a morpheme to the main verb.

The lexical rule for a negative verb will add a semantic relation in much the same way as the potential form (for can as verbal inflection) described above, so follow the directions there about selecting a supertype for the rule.

This time, the C-CONT RELS and HCONS lists, will each have one item on them:

RELS < ! adv-relation &
         [ PRED '_neg_r_rel,
           ARG1 #harg ] ! >

HCONS < ! qeq &
         [ HARG #harg,
	   LARG #larg ] !>

In addition, the C-CONT.HOOK.LTOP should be identified with the LBL of the adv-relation and the C-CONT.HOOK.INDEX with the ARG0.
Add an instance for your lexical rule to irules.tdl, with the appropriate spelling change information.
Constrain your lexical rule to apply only to verbs, and test this. Add the sentences you used to test it to your master testsuite file.
If you have other verbal inflection in your language, determine which lexical rule has to go first, and constrain the rules to only apply in that order. Make up nonsense forms with the affixes attached the other way around, and make sure that they don't parse. Add these sentences to your master testsuite file. If your other affixes attach to the other end of the verb, you'll want to constrain the order anyway, or you will end up getting double parses.
Parse your translation of It doesn't hurt me. and see if you get the right semantics. Debug as necessary.

Two-part negation

Use this version if your language expresses negation with both an affix on the verb and an adverb (e.g., French ne ... pas). If both elements are arguably affixes, you probably just want to write a pair of lexical rules, i.e., take the "Negation as a verbal affix" route, but write two rules and make sure you can require that they both apply or neither apply.

The strategy here is going to be add the affix with a lexical rule similar to the one above, but to have it change the COMPS value and not add any semantics. The COMPS list will be the same as the input's COMPS list, with the addition of a negative adverb.
We're assuming that the second part of the negation has an independent life as a negative adverb for constituent (i.e., not sentential) negation. This seems to work for French at first glance, I'd be curious about other languages. That adverb will have to have constraints on its MOD value that keep it from modifying finite verbs (which would give sentential negation). However, if you don't have any head-modifier rules in your grammar, you don't need to worry about that yet.
The negative adverb needs some kind of distinguished value (a feature inside HEAD, and in particular, HEAD.KEYS.KEY might be a good candidate) so that the rule won't license verbs just picking up any adverb as a complement.
The inflected verb will "hand" its LTOP value to the negative particle, and adopt the negative particle's LTOP value as its own. Regular semantic composition should take care of the rest.
Again, you'll need to look at the lexrule types and pick an appropriate supertype. Since we're changing both VAL.COMPS and CONT.HOOK, you might need to create your own supertype. Talk to me :).
Test your grammar: Try parsing your translation of It doesn't hurt me. and see if you're getting the right semantics. Test sentences with each of the two parts of the negation independently, and verify that they don't parse. Try putting the two part negation on a non-verb, and verify that it doesn't parse. Add these sentences to your master testsuite file. Debug as necessary.

Test your grammar and try generating!

Use your master testsuite file to make sure you haven't lost any coverage from previous labs. Debug as necessary.
Try parsing I can eat glass. and It doesn't hurt me. and then generating from the semantic representations your grammar produced.
(If you see the error "probable circular lexical rule", it means your lexical rule is morphosyntactically capable of applying to its own output. Since the generator isn't constrained by any surface forms, it can keep adding inflectional endings...)
To receive full credit on this lab, your grammar will need to be able to generate back the input string for these two sentences, and do so without generating too much other garbage.

Test suite suggestions

If you had to add a special form of the verb eat to show up as the complement of can, add examples testing whether the other form can show up there and whether only the appropriate form(s) can show up in unembedded contexts.
If you had to add lexical rules (for either part), add examples testing whether the rules apply only to verbs and their order with respect to other lexical rules.
If your negative element is an adverb with restricted distribution, add examples testing whether it can show up in all and only the positions permitted.
If your negative element is a complement of the main verb, but only finite main verbs, add examples testing whether it can show up with non-finite verbs as well.
Create sentences with both can and not to test their interaction.

Write up

Describe the facts of sentential negation in your language. Used glossed examples.
Describe how you implemented or attempted to implement sentential negation. If you were able to use of the scenarios described above, specify which one. If you had to add something, or if your language is completely different from any of the choices above, describe in detail what types, contraints, rules you had to add.
Describe the current coverage of your grammar wrt to the sentential negation facts of the language (syntactic and semantic: are you getting the right strings and only the right strings? Do they get the right meaning?). Make sure these facts are represented in your test suite. If you don't have complete coverage, speculate as to what you need to do to get there. If there are particular problematic strings, include them in the write up so I can try parsing them and give you feedback.
Describe the facts of how the equivalent of can is expressed in your language. Use glossed examples.
Describe how you implemented or attempted to implement can If you were able to use of the scenarios described above, specify which one. If you had to add something, or if your language is completely different from any of the choices above, describe in detail what types, contraints, rules you had to add.
Describe the current coverage of your grammar wrt to the facts of how can is expressed in your language (syntactic and semantic: are you getting the right strings and only the right strings? Do they get the right meaning?). Make sure these facts are represented in your test suite. If you don't have complete coverage, speculate as to what you need to do to get there. If there are particular problematic strings, include them in the write up so I can try parsing them and give you feedback.

Submit via ESubmit

Be sure your matrix folder includes your test suite and your write-up.
Consider removing the doc/ subdirectory in order to save space on E-Submit.
Compress the folder, and upload it to ESubmit.
Submit it by midnight Sunday night (preferably by Friday evening :-).

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