Linguistics 471: Grammar Engineering

Lab 2 Due 4/18

Read all the way through the assignment once before starting it. Also, note that you'll be asked to turn in three small write-ups this time. They're mentioned in the assignment, of course, and then I remind you again in the instructions under "Submit via ESubmit"

Background

Tasks

Get an updated copy of matrix.tdl

Emily has fixed another bug in the Matrix. Down load a fresh copy here: matrix.tdl. (Without this bug fix, the covert-det rule in this assigment won't work properly.)

Take a look at the current state of affairs

Add relation names to your noun and verb lexical entries

Add types for relation names for determiners

In order to support our goal of machine translation, we need to allow for underspecified determiners in some languages. That is, for a language that doesn't necessarily mark definite v. indefinite determiners, we'd like the quantifier relation to be compatible with either definite or indefinite. To achieve this, we will write a small subhierarchy under predsort. Likewise, some languages have a three-way distinction among demonstratives, while others only a two-way.

Add PRED values to your determiner lexical entries

Add a rule for determinerless NPs

One of the requirements on well-formed MRSs is that each ARG0 of a noun-relation be bound by a quantifier (i.e., also be the ARG0 of a quant-relation). If your noun phrases contain overt determiners (and you're using the basic-determiner-lex type provided by the Matrix) this is already the case. For noun phrases that don't contain overt determiners, we'll need to add a non-branching rule which fills in the appropriate semantics.

In many languages, determiners are optional only with some kinds of nouns, and non-optional with others. If determiners are always optional in your language, that is, if any given noun can appear without a determiner, then you don't need to do this part. Read it anyway though :-). The general strategy is going to be to define two types of nouns, ones with optional determiners and one with obligatory determiners. We will indicate optionality with a feature OPT (appropriate objects of type synsem and therefore found at the path SYNSEM.OPT). Nouns which require determiners will say that the element of their SPR list is [OPT -]. Nouns which can optionally appear without determiners won't say anything about OPT. The covert-det rule will say that the SPR requirement of its head daughter is [OPT +]. This will be incompatible with those nouns that say [OPT -] but compatible (of course) with those that don't mention OPT at all.

(Nouns like proper names and pronouns which generally can't take determiners, i.e., must undergo the covert-det rule, need to have a SPR requirement which is incompatible with any overt determiner, but still compatible with the covert-det rule, or perhaps a special covert-det rule just for proper names and pronouns. If your only case of determinerless NPs is this one, talk to me.)

Try generating from the semantic representation

Submit via ESubmit


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