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<?xml version="1.0" standalone="yes"?> <Paper uid="W98-0708"> <Title>I I I I I I I I I I I I I I I I I I I Linking WordNet Verb Classes to Semantic Interpretation</Title> <Section position="3" start_page="58" end_page="62" type="metho"> <SectionTitle> 2 The syntax of roles </SectionTitle> <Paragraph position="0"> The syntax of roles in the predicates that will be defined below is ~ven by the cfg grammar on the next page. Each thematic role is followed by any number of list pairs. The first list contains the selectional restrictions, a subset of the ontological categories in WordNet, in order of preference (Will<s, 1975) for ! ! the thematic role, and the second list contains the syntactic relations (henceforth, SRs) that may realize the thematic role. For any given sentence, only one of the SIRs in the list realizes the role. An ontological category preceded by the sign %&quot; in a selectional restriction means that any noun sense that is subsumed by the semantic category preceded by &quot;-&quot; does not realize that thematic role.</Paragraph> <Paragraph position="2"> The entry obj refers to the first postverbal NP, obj2 to the second postverbal NP. Subj-if-obj refers to the subject of a sentence that also has an object (the verb is used transitively), and subj-if-no-obj refers to the subject of a sentence containing no object (the verb is used intransitively). Obj-if-obj2 refers to the obj of a sentence having also an obj2 (the verb is used ditransitively). Thus, subj refers to the subject of a sentence without expressing any context about the transitivity or intransitivity of the verb. 3 Verbs in which the agent causes a change of location of something else In (Gomez, 1998), we provide an analysis of verbs in which an animate agent changes location. We start explaining the predicate cause-to-change-location depicted on top of the next column. The primary event expressed by this predicate is a cause of change of location of something other than the agent; although the agent may have also changed location. In &quot;Kelly carried the flowers to the table&quot; and in &quot;Kelly drove John to school,&quot; the agent has also been moved, but the primary event is the fact that Kelly causes a change of location of the flowers and John, respectively. The WordNet synset &quot;move2, displace, make move - (cause to move)&quot; is coalesced, in principle, into this predicate. But, also many of the sub-classes of &quot;move3, change position&quot; are mapped into subpredicates of this predicate. (Physical-thing has been abbreviated to phy-thing in some entries for space reasons.) The urn-map entry means that all verb forms under the synset move2 are in principle coalesced into the concept cause-to-change-location.</Paragraph> <Paragraph position="3"> However, subpredicates of this predicate will be recognized as explained below. The category human- null agent subsumes human and social-group. The role inanimate-cause stands for an agent that is not an animate being or an organization. The syntactic realization of this role is always a sub j-if-obj. Because the agent of this predicate is also realized by subj-ifobj, and the ontological category animal and human-agent are subsumed by physical-thing, then in &quot;Beth put the books on the table,&quot; both the agent and the inanimate-cause will match. The impasse is solved by preferring the agent over the inanimate-cause.</Paragraph> <Paragraph position="4"> The theme is realized by obj, and is also realized by a subj if the verb is used intransitively. Thus, for &quot;The wind has knocked down many apples from the tree,&quot; &quot;the wind&quot; is the inanimate-cause, &quot;many apples&quot; is the theme and &quot;from the tree&quot; is the source. In &quot;The leaves have moved,&quot; the &quot;leaves&quot; is the theme, and the agent, or inanimate-cause is unknown. In &quot;The tractor has pulled the tree&quot; &quot;the tractor&quot; is the instrument, and the agent is unknown. The different ways of expressing a path, namely toward-goal, neargoal, etc. have been collapsed here into goal for space reasons. Actually, there is one role for each preposition that expresses a different spatial relationship.</Paragraph> <Paragraph position="6"> (goal(location phy-thing)((prep to tovaxds toward in through into back-to along over beside above by on under below throughout beyond past across near up)))</Paragraph> <Paragraph position="8"> The first subclasses of move2 analyzed by Word-Net are the senses of &quot;transport.&quot; The subclasses formed by the synsets &quot;transportl (move something or somebody around; usually over long distances),&quot; &quot;transport2, carry (move while supporting, either in a vehicle or in one's hands or on one's body),&quot; &quot;transport3, send, ship - (transport commercially)&quot; and &quot;transmit, transfer, conduct, transport5, channel, channelize&quot; are mapped into subpredicates of the predicate transport which is: <other transport predicates here> The goal, besides being realized by the same prepositions as those for cause-to-change-location, is also syntactically realized by an indirect object (obj-ifobj2), e.g., (1)&quot;Susan brought her children a book from Harvard.&quot; Thus, the theme can be realized by an obj2 or by an obj, e.g., &quot;Mary brought her children from school.&quot; This is the analysis that this work provides for all double object verbs. Because the semantic interpreter delays commitment until the end of the clause, the interpreter does not have to reanalyze.</Paragraph> <Paragraph position="9"> The predicate pull, which corresponds to the synset &quot;pulll, draw, force,&quot; and that contains such forms as &quot;jerk,&quot; &quot;twitch,&quot; &quot;trail,&quot; &quot;drag,&quot; etc. is:</Paragraph> <Paragraph position="11"> Next, WordNet includes a large class of forms under the synset &quot;put, set, place, pose, position, lay; also with abstract objects and locations.&quot; This work differs from WordNet and does not include abstract objects as themes of this predicate. The predicate put is:</Paragraph> <Paragraph position="13"> (goal(location physical-thing) ((prep on in towaxds through into back-to along over beside above by under below throughout beyond past across near))) (instrument (instrumentality) ((prep with))) (source (nil) (nil))\] This predicate illustrates two points. First, its goal is not expressed with the preposition '%o,&quot; e.g., *Mary placed/arranged/put/etc the books to the table. Second, the source is not realized by any syntactic relation (Levin, 1993). That is why the source entry is nil for the selectional restriction and the syntactic relation in order to indicate that this predicate does not inherit a goal from its ancestors. The concern here is not syntactic subcategorization of the verb forms, which is handled by the parser, but attachment of PPs. Any PP whose preposition appears in th~ entry of a thematic role is going to be attached preferentially to the verb. Thus, in &quot;Connie put the reports from MIT on the shelf,&quot; the prepositional attachment algorithm should not consider &quot;from MIT&quot; as a possible complement of &quot;put.&quot; WordNet includes several subclasses of putl, all of which have been mapped to subpredicates of put. Some verb forms under this predicate, such as &quot;put&quot; and &quot;place,&quot; realize their goal with ~at&quot; phrases. This fact is represented in the verb forms themselves. The next major subclass of move2 is under the synset &quot;propell, impel, move forward,&quot; which includes the subclasses &quot;hitl cause to move by striking&quot;) and &quot;throw&quot; verbs. The predicate propel is depicted on the next column. Most of its thematic roles are inherited from cause-to-change-location, illustrating how relatively easy it is to build these entries once the predicates for the main subclasses have been constructed. The goal of this predicate is also realized by an indirect object (obj-if-obj2), e.g., ~Sue threw the pitcher a ball.&quot; This class of verbs has an argument realized by the preposition &quot;against,&quot; that has been mapped into the role contact-goal, a refinement of the role goal, meaning that the theme contacted the goal</Paragraph> <Paragraph position="15"> ((prep to on in through towards into back-to along over beyond past across by near at))) (contact-goal(physical-thing)(against))\] The subclass formed by hitl, not to be confused with &quot;hit3 - ideal a blow to; He hit her hard in the face),&quot; becomes \[cause.to-move-by-biting (is-a(propel))(wn-map(hitl))\], the one formed by &quot;throwl, project through the air&quot; becomes \[throuJ(isa(propel))(urn-map(throwl))\]. A subclass of throwl is formed by those verbs that Levin (Levin, 1993) calls ~pelt&quot; verbs (&quot;buffet,&quot; &quot;bombard,&quot; &quot;pelt,&quot; &quot;shower,&quot; &quot;stone,) in which the goal is realized by obj and the theme by a &quot;with&quot; phrase, e.g., &quot;Beth pelted Chris with snowballs.&quot; Of these, WordNet does not include &quot;shower&quot; and &quot;stone&quot; as forms under peltl.</Paragraph> <Paragraph position="16"> Some classes in move2 and move3 are not mapped into subpredicates of the generic predicate causeto-change-location. The reasons for not mapping a WordNet subclass into a subpredicate of the generic predicate for the WordNet class are any one of the following: a) these predicates do not share the thematic roles of the generic predicate, b) the primary event expressed by these subpredicates is not that of the generic predicate, or c) the ontological categories in the selectional restrictions of the generic predicate do not subsume those in the subpredicates. One major subclass of move2 that clearly is not a sub-</Paragraph> <Paragraph position="18"> predicate of cause-to-change-location is grouped under the synset &quot;transfer, convey, transmit, communicate, bring,&quot; and includes such forms as &quot;relay,&quot; &quot;request,&quot; &quot;demand,&quot; &quot;expect,&quot; &quot;require,&quot; &quot;beg,&quot; and many others. The theme of the predicate for this class is not a physical-thing, but an abstract thing, idea or a proposition, which is many times realized by a sentential complement. Two other strongly related subclasses of move2 that are not subpredicares of cause-to-change.location are grouped under the synsets &quot;expel, eject, chuck out, exclude, throw out, kick out, turf out, boot out, turn out - (from a place),&quot; and &quot;expel, throw out, kick out - (as from a country).&quot; The first subclass includes such forms as &quot;evict,&quot; &quot;exorcise,&quot; and the second subclass includes &quot;expatriate,&quot; &quot;deport,&quot; &quot;disbar,&quot; &quot;extradite,&quot; &quot;ostracize,&quot; and others. The relation between the theme and the agent in the predicates underlying most of these forms is an abstract relation rather than a physical relation. The analysis provided for these classes has been to create a subpredicate of action, called expel-human-agent, which coalesces the two synsets discussed above plus a synset of remove, remove2, a class by itself, &quot;remove - (remove from a position or an office).&quot; Remove2 includes such forms as &quot;fire,&quot; &quot;lay off,&quot; etc. This generic predicate is analyzed into several subpredicates.</Paragraph> <Paragraph position="19"> Another major subclass of move2 that is not mapped into a subpredicate of cause-to-change-location is grouped under the synset &quot;separate2, disunite, force apart, divide, part, take apart, pull apart - He separated the fighting children; Moses parted the Red Sea,&quot; and includes such forms as &quot;compartmentalize,&quot; &quot;polarize,&quot; &quot;disarticulate,&quot; &quot;disconnect,&quot; &quot;cut&quot; and its subclasses, and many others. The primary event of this subclass is not a cause-to-change-location, although one may be implied. Some of these forms can be used in the causative/inchoative alternation, e.g., &quot;The cream separated from the milk,&quot; and in the middle alternation, e.g., &quot;Cream separates easily from milk&quot; (Levin, 1993). Separate2 is analyzed as a subpredicate of cause-a-change-of-state, and coalesced with some other synsets of &quot;separate&quot; which are classified by WordNet as subclasses of change1, cause a change of state. Another subclass of move2 that has required a special analysis is that of &quot;chase away, drive out, turn back, drive away, dispel, drive off, run off&quot; in which the agent is causing the theme, an animate being, to move away from the agent's location.</Paragraph> <Paragraph position="20"> In move3, some individual forms and some sub-classes are mapped into the predicate move-bodypart, a subpredicate of action. Some of these sub-classes are: &quot;move involuntarily, move reflexively (move in an uncontrolled manner),&quot; &quot;dance, do a dance ...&quot; and a few others.</Paragraph> <Paragraph position="21"> The following predicates do not come from sub-classes of move2 or move3, but from change1 (cause a change of state). However, they are analyzed as sub-classes of cause.to-change-location. The first predicate fill-or-load, depicted on the next column, coalesces the synsets: &quot;fill1, fill up, make full,&quot; and &quot;flU2, fill up, become full.&quot; Of these, flU1, which is a subclass of change1 contains most of the forms, including all the &quot;load&quot; verbs. Fill2, a subclass of change2 (undergo a change) contains two forms.</Paragraph> <Paragraph position="22"> Note the different syntactic realizations of this predicate, as exemplified by &quot;The farmer loaded the truck with hay&quot; and &quot;John loaded the tractors into the ship.&quot; It is not very helpful to include inntrumentality as one of the selectional restrictions of the theme because anything can be loaded. However, substance could help to choose the correct sense of certain nouns, because it is a selectional restriction used frequently with &quot;fill&quot; verbs. The predicate empty that coalesces the synsets &quot;empty1, make empty, make void&quot; and &quot;empty2, become empty, become void, discharge&quot; becomes a subpredicate of removephysical-thing, described below. The obj-if-with relation in the goal role means that this role can be realized by an obj if there is a with-phrase. For instance, &quot;Kelly loaded the truck with hay.&quot;</Paragraph> <Paragraph position="24"> obj-if-with (prep into on onto in)))\] The next major class is grouped under the synset of &quot;remove1, take, take away - (remove something concrete, as by lifting, pushing, taking off, etc.; or remove something abstract; remove a threat ...).&quot; Remove2 was analyzed above in the predicate expelhuman. Remove1 forms a class by itself in WordNet.</Paragraph> <Paragraph position="26"> Removel contains many subclasses, most of which are mapped to subpredicates of remove-physicalthing. Remove3: &quot;get rid of, remove,&quot; also forms a class by itself and is analyzed as a subpredicate of remove-physical-thing. WordNet does not include &quot;rid&quot; as a subordinate of any of the &quot;remove&quot; senses, but as a small class by itself containing nine forms.</Paragraph> <Paragraph position="27"> This work maps &quot;rid1, free, disembarrass&quot; to r/d, a subpredicate of remove-physical-thing, in which the theme is realized by an &quot;of&quot; phrase, and the source by obj, e.g., &quot;He rid the city of rats.&quot; Empty, another subpredicate of remove-physical-thing, may</Paragraph> <Paragraph position="29"> also realize its theme and goal with an &quot;of&quot; phrase and obj, respectively. Some forms under this sub-class are used in the sense of &quot;firing somebody.&quot; Rather than to reclassify these forms, a meaning postulate connects this predicate to the predicate expel-human-agent, explained above, if its theme is the concept human. This subclass also contains a subclass that does not express a source, but a goal.</Paragraph> <Paragraph position="30"> This subclass is: &quot;abandonl - (We abandoned the old car in the empty parking lot),&quot; which includes such forms as &quot;chuck,&quot; &quot;ditch,&quot; &quot;dispense with,&quot; and others. AbandonS: &quot;abandon, forsake, desolate, desert, lurch - (leave someone who needs or counts on you);&quot; which is a suclass of &quot;leave2&quot; is also coalesced into the the predicate: \[abandon-phy-thing- null The major subpredicates are give and get which are listed last. The generic predicate transfer-of-possession is described below. There are two events in a transfer of possession. The theme refers to the thing obtained or received by the agent of the primary event, and the co-theme to the thing obtained or received by the agent of the secondary event. A meaning postulate infers the predicate and its roles for the secondary event. The exclusionary semantic categories in the co-theme are to impede indetifying a \[for NP\] as a co-theme when it is a to-poss, e.g., &quot;He bought a book for Mary/20 dollars.&quot; physical-thing thing) ( (prep for))) \] The subpredicate give is depicted below. The only difference between give and its generic predicate is that it does not have a co-theme. The synset give3 has many verb forms. Some of them are analyzed below.</Paragraph> <Paragraph position="31"> \[give</Paragraph> <Paragraph position="33"> The predicate feed depicted below has some interesting garden path constructions. Compare &quot;Beth fed the frogs insects&quot; to &quot;Ann fed the frogs to the snakes&quot; and &quot;Kathy fed the frogs.&quot;</Paragraph> <Paragraph position="35"> The synsets supply1 and provide2 are mapped into two predicates, provide and provide-inanimate-cause depicted on the next page. The predicate provide-inanimate-cause subsumes all those predicates in which the thing that causes the transfer is not an animate being, but an inanimate thing, e.g., &quot;The river provides water to many cities.&quot; The syntactic relation obj.if-with indicates that the role to-poss can be realized by an obj if this is followed by a \[with NP\]. This is necessary in order to handle the sentence &quot;France also provided the missionary with new churches.&quot; The next mayor subpredicate of transfer-of-possession is get-something depicted below. Its synset, getl, is a unique class in WordNet.</Paragraph> <Paragraph position="36"> One of the major subclasses of get-something is the predicate capture-an-animal which has a very simple entry.</Paragraph> <Paragraph position="38"> (from-poss (human-agent animal phy-thing thing) ((prep off from out-of))) Most of its subpredicates require a human as agent, but some take an animal as agent. Another class is formed by the verbs belonging to the synset receivel and receive2 whose predicate is: \[receive-something (is-a (get-something)) (un-mapCreceivel) (receive2)) (theme(auard -human-agent physical-thing -perception thing) (obj obj2))\] The exclusionary categories human-agent and perception are intended to exclude the sense of receiving, or welcoming somebody, and that of receiving experiences, or experiencing something, from this predicate. Those senses are mappped into their own predicates.</Paragraph> <Paragraph position="39"> The synset winl (be the winner in a contest or competition) that is a unique class in WordNet has been mapped into the predicate win-at-an-event which has become a subconcept of get-something. The synset win2 (win something) is mapped into the predicate gain-something. Two other subpredicates of get-something whose synsets form unique classes in WordNet are gather-things (gatherl) and get-by-/orce-or-illegally (takel4).</Paragraph> </Section> class="xml-element"></Paper>