1Week 3a. θ-roles, featurechecking3.5-3.6CAS LX 522Syntax IPreviously, in LX522… We left off last time exploringthe idea that sentences arebuilt from syntactic objectsby using the operationMerge, taking two syntacticobjects and forming a newone from them. Big picture: What we’retrying to model is a system thatcan construct all—andonly—those strings of wordsthat correspond to sentences ofa language (e.g., English). If wesucceed, this system is (at leastisomorphic to) what we knowwhen we know the language.B CD EPreviously, in LX522… So far, we have: The lexicon (containing words,bundles of features) Merge (forms a syntactic objectfrom two others). Merging two objects yields anew object that has theproperties of one of the twoobjects. Merging eat and lunch yields aobject that has the same kinds ofproperties as eat. The object whose featuresdetermine the features of thenew object (project) is the headof the new object—the mostimportant component. The question now is: how doesMerge know which one is thehead?B CD EWho’s in charge here? The idea we are goingto pursue here is thatone of the two objectsneeds Merge tohappen—and theneedy one is the head. What does it mean to“need to Merge”? Consider hit. This can’treally stand on its own. Itdoesn’t mean anything(its truth can’t beevaluated) withoutproviding a hitter and ahittee.B CD EPredicates, arguments, andpropositions Conventional wisdom has it that a sentenceneeds a subject and a predicate. The idea is that the sentence expresses thatthe property signified by the predicateholds of the subject. Pat danced. Danced is the predicate, it’s a property thatPat, the subject, has (if the sentence is true).Something that can be true or false, a“complete thought”, is a proposition.Verbs and arguments Some are basically complete as they stand. Rain: It rained. Some have only a subject, they can’t have anobject—the intransitive verbs (1-placepredicates). Sleep: Bill slept; *Bill slept the book. Some also need an object—the transitive verbs(2-place predicates). Hit: *Bill hit; Bill hit the pillow. Some need two objects—ditransitive verbs (3-place predicates). Put: *Bill put; *Bill put the book;Bill put the book on the table.2Verbs and arguments The “participants” in an event denoted bythe verb are the arguments of that verb. Some verbs require one argument, somerequire two arguments, some require threearguments, some require none. Intuitively, the number of arguments is thenumber of things that a verb needs in orderto make a proposition (something that canbe either true or false).Predicates We will consider verbs to be predicateswhich define properties of and/or relationsbetween the arguments. Bill hit the ball There was a hitting, Bill did the hitting, the ball wasaffected by the hitting. Different arguments have different roles inthe event. (e.g., The hitter, the hittee)Thematic relations It has come to be standard practiceto think of the selectional restrictions interms of the thematic relation that theargument has to the verb—the role itplays in the event. One thematic relation is agent of anaction, like Bill in: Bill kicked the ball.Common thematic relations Agent: initiator or doer in the event Theme: affected by the event, orundergoes the action Bill kicked the ball. Experiencer: feel or perceive the event Bill likes pizza. Proposition: a statement, can betrue/false. Bill said that he likes pizza.Thematic relations Goal: Bill ran to Copley Square. Bill gave the book to Mary. (Recipient) Source: Bill took a pencil from the pile. Instrument: Bill ate the burrito with a plastic spork. Benefactive: Bill cooked dinner for Mary. Location: Bill sits under the tree on Wednesdays.Thematic relations Armed with these terms, we candescribe the semantic connectionbetween the verb and its arguments. Ray gave a grape to Bill. Ray: Agent, Source, … A grape: Theme Bill: Goal, Recipient, …3Intransitives:Unergatives and unaccusatives For intransitive verbs (1-place predicates),there are two primary classes: Unergatives: Agent assigned to argument. Pat danced. Pat yodelled. Unaccusatives: Theme assigned to argument. Pat tripped. The boat sank. Basically what you’d expect consideringthe normal transitive (2-place) verbs thathave an Agent and a Theme. The naming of these classes is not my fault.θ-roles An argument can participate in several thematicrelations with the verb (e.g., Agent, Goal). In the syntax, we assign a special connection tothe verb called a “θ-role”, which is a collection ofthematic relations. For the purposes of syntax, the θ-role (the collectionof relations) is much more central than the actualrelations in the collection.θ-roleAgentSourceθ-roles We will often need to make referenceto a particular θ-role, and we will oftendo this by referring to the mostprominent relation in the collection. For example, in Bill hit the ball, we saythat Bill has the “Agent θ-role”,meaning it has a θ-role containing theAgent relation, perhaps among others.The Unique θ Generalization Each θ-role must be assigned to aconstituent, but a constituent cannot beassigned more than one θ-role. (a.k.a. “the θ-criterion”) Verbs have a certain number of θ-rolesto assign (e.g., say has two), and each ofthose must be assigned to a distinctargument.C-selection Verbs are recorded in the lexicon with the θ-roles they assign as part of their meaning. But, (some) verbs can assign the same type of θ-role to different categories of argument: Pat felt a tremor. Pat felt uncomfortable. Pat felt thatChris had not performed well. Pat is the Experiencer; a tremor (noun), uncomfortable(adjective), or that…well (sentence) is the Theme/Source. So θ-role does not determine syntactic category. And syntacticcategory certainly does not determine θ-role. Pat kicked a pail. *Pat kicked unhappy. *Pat kicked thatthe earth is round. So verbs also need to be recorded with information about thesyntactic categor{y/ies} they combine with.C-selection (“Subcategorization”) Kick needs a nominal object. Pat kicked the pail. Kick has a [V] category feature, but also needsto have an [N] category feature in some formto specify that it needs a nominal object. BUT—We don’t want to
View Full Document