Basic Definition: An agent volitionally causes an event.

Examples:

• John broke the vase. (Dorr - Agent)
• Henry pushed the door open and went in. (Gildea - Agent)
• Henry pushed/broke the door. (VerbNet - Agent)

Sometimes it is not clear that volition and cause are involved in an event. For example, "They met in the library" could mean that they met on purpose or by accident. In this case, some linguists resort to identifying which participant in the event is the most like an agent. The participant that is most like an agent is volitional, sentient, causing, and having independent existence. The last one requires an explanation. In "I built a house" the house comes into existence as a result of building, but I exist all along, independent of the building event.

References: Dowty's proto-agent; Van Valin's macro roles.

Basic confusions and how to resolve them:

• Agent and Experiencer: If the verb is about cognition (think, know), perception (see, hear, taste), or emotion (fear, enjoy), then use experiencer instead of agent.

• Agent and Experiencer: If the verb is about something that your body does (sweat, shiver, bleed), then use agent. (See EXP below. This decision was made on the basis of syntax, not semantics, so I could be convinced to change my mind.)

• Agent and Theme: Things that change location are themes. But what if the thing that changes location is the same as the thing that causes a change of location as in "We ran to school"? We volitionally cause the change of location (agent) and we also change location (theme). For now, call it an agent.

• Agent and Instrument: In "The key opened the door", the key causes the door to open in some sense. However, it is not volitional. Fillmore (1968 or some other paper from a long time ago) proposed that the key is not an agent. His evidence for this conclusion was that you can't say "John and the key opened the door". The reason this sounds bad is that John and the key do not really have the same role. John is an agent, and the key is an instrument.

• verbs often have two senses, agentive (I tasted the wine by swirling and sipping) and non agentive (When I fell into the ocean, I tasted salt water). Comrie points out that these are treated differently in French causatives: "par" can be used for agents and "a" for non agents: J'ai fait gouter le vin a/par Jean. If we treat all instances as experiencer verbs, we will lose this distinction.

• Motion verbs can also be agentive or non-agentive: fall, roll, etc. when used with human subjects the verbs can act unaccusative or unergative.

THM: theme

Basic Definition: Theme is about being, changing, or being affected. It is more abstract than the other roles, so here are some specific cases. Use the role THM when the verb is about:

• location:
  • The clock (THM) sits on the shelf.

• change of location:
  • The car (THM) turned into the driveway,
  • We pushed the car (THM) into the driveway.

• attaching:
  • I attached/sewed the pocket (THM) to the dress.

• existence:
  • Problems (THM) exist.
  • There are problems (THM).

• changing existence/creating:
  • Several events (THM) occurred.
  • Something (THM) happened/arose/came up.
  • Sam made a cake (THM).
  • Sam baked a cake (THM).
  • Sam sewed a dress (THM).

• appearing and disappearing:
  • A sail (THM) appeared on the horizon.
  • The sail (THM) disappeared from the horizon.

• being in a state:
  • The book (THM) is red.

• changing state:
  • The liquid (THM) turned red.
  • The glass (THM) broke.
  • The pumpkin (THM) turned into a coach.

• being in possession:
  • In our definitions, this is a POS, not a theme.
  • I have/own/possess a book (POS).

• being contained: In our definitions, this is a POS, not a theme.
  • The box contains books (POS).

• changing possession, including buying and selling:
  • We gave/handed books (THM) to the students.
  • They awarded the prize (THM) to Sam.
  • We bought/sold old books (THM) for 50 cents each.

• being communicated:
  • We told stories (THM) to the children.
  • We sang songs (THM) to the children.
  • We said it (THM) to them.
  • We taught them linguistics (THM).

• extending:
  • The road (THM) goes to Pittsburgh.
  • The road (THM) runs along the river.
  • The string (THM) extends/reaches across the room.
  • The string (THM) touches the wall.

• I kicked/poked/prodded the ball (THM).

• John (THM) went to school. (Dorr - Theme)
• John broke the vase (THM). (Dorr - Theme)
• John memorized his lines (THM). (Dorr - Information)
• She buttered the bread with margarine (THM). (Dorr - Instrument)
• John wanted to go home. (Dorr - Prop)
• As soon as a character lays a hand on this item, the skeletal Cleric grips it (THM) more tightly. (Gildea - Patient)
• It says that rotation of partners does not demonstrate independence (THM). (Gildea - Proposition)

• He said, ``We would urge people to be aware and be alert with fireworks (THM) because your fun might be someone else's tragedy.'' (Gildea - Topic)

Possible confusions and advanced cases how to resolve them:

• See AGT for possible confusions of THM and AGT.

• Covering and filling verbs:
  • (i) The baby smeared peas on the wall.
  • (ii) The baby smeared the wall with peas.

EXP: Experiencer:

Basic Definition:

An experiencer is a cognizer, emoter, or perceiver. An experiencer has no causation, but is sentient and exists independently. (See AGT.) Typically an experiencer is the subject of verbs like feel, hear, see, sense, smell, taste, notice, discern, detect, glimpse, hear, regard, seek.

Advanced Comments:

The reason that experiencer is distinguished from Agent, is that there is often different syntactic behavior associated with experiencers. For example, they may have a dative or instrumental case marking; see the comment about French causatives above; verbs with experiencers instead of agents may act unaccusative.

Examples:

• John (EXP) heard the vase shatter. (Dorr - Experiencer)
• It may even have been that John (EXP) anticipating his imminent doom ratified some such arrangement perhaps in the ceremony at the Jordan. (Gildea - Experiencer)

• In languages where agents have different behavior than experiencers, I think that things that your body does (e.g., shiver, sweat, and bleed) act like they have agents, and not experiencers. (Since this is a syntactic criterion rather than a semantic one, I could change my mind about it.)

• It is sometimes hard to decide whether or not something is a cognizer. For example, is planning a cognitive event or an activity (making charts, writing letters, having meetings)?

• Perception vs activity: Hearing is definitely perception, but listening might be an agentive activity. Scrutinizing could also be an activity, although it may include perception.

INS: Instrument

Basic definition:

An instrument should have causation but no volition. An instrument can be wielded by an agent, but an instrument can also occur without an agent.

Examples:

• Prototypical instruments:
  • The Hammer (INS) broke the vase. (Dorr - Agent) (VerbNet - Instrument)
  • She hit him with a baseball bat (INS).(Dorr, VerbNet - Instrument)

• Real :) instruments:
  • In the children with colonic contractions fasting motility (INS)did not differentiate children with and without constipation. (Gildea - Instrument)
  • If this is the case can it be substantiated by evidence from the history of developed societies (INS).(Gildea - Force)

• Cause of an emotion:
  • Jeez, that (INS) amazes me as well as riles me. (Gildea - Cause)
  • His death (INS) saddened us. (VerbNet - Cause)

• Instrument and Perceived: Note that the definition of instrument includes causes of emotions, but does not include things that are perceived. Recall that there are three kinds of experiencers: emoters, perceivers, and cognizers. INS goes only with emoters. PRC goes only with perceivers.

• Agent and Insrument: See notes under AGT.

PRC: Perceived

Basic Definition:

• If the verb is about perception, the PRC is the thing that is perceived.

• Perceived: Refers to a perceived entity that isn't required by the verb but further characterizes the situation. The perceived is neither causally affected nor causative. It doesn't experience a movement or change in state. Its volition and sentience are irrelevant. Its existence is independent of an experiencer. PRC is often paired with EXP.

• He saw the book (PRC). (Dorr - Perceived)
• The cat's fur (PRC) feels good to John. (Dorr - perceptual modifier)
• What is apparent is that (PRC -- whole embedded clause) this manual is aimed at the non-specialist technician possibly an embalmer who has good knowledge of some medical procedures. (Gildea -Percept)
• Rex spied out Sam Maggott (PRC) hollering at all and sundry and making good use of his over-sized red gingham handkerchief. (Gildea - State)

• She saw the play.
  • Is seeing a play an activity that includes buying a ticket, going to a theater, sitting down, etc. It might involve more than perception.
• He looked into the room. (Dorr - Perceived)
  • Look may be something that you do. Not just perception.
• She imagined the movie to be loud. (Dorr - MOD-PROP)
  • cognition or perception?

PRD: Secondary Predicate

Basic Definition:

PRD should be used for secondary predicates. Secondary predicates describe the subject or object of the verb. For example, in "The coroner pronounced him dead", "dead" is a secondary predicate that describes the direct object, "him". The reason it is called a secondary predicate is that the primary predicate is the verb "pronounce."

Examples:

• We considered him a fool (PRD). (Dorr - Pred)
• We pronounced him dead (PRD). (Dorr - Pred)
• She acted happy (PRD). (Dorr - Pred)
• The nation elected him president (PRD). (Dorr - Mod-pred)
• They worshiped him as their leader (PRD). (Dorr - Mod-pred)
• She imagined him as a prince (PRD). (Dorr - Mod-pred)
• He arrived drunk (PRD).

PRD and GOL: Some secondary predicates describe resulting states. For example, in "The liquid turned red", there is some event of changing color and the result of the change is that the liquid is red. A result of a change is a goal (GOL), not a PRD.

• Examples
  • The liquid turned red (GOL).
  • He became a teacher (GOL).
  • The carpenter hammered the nail flat (GOL).

SRC: Source

Basic Definition:

A source is where something starts.

Examples:

• Starting point of a change of location:
  • He ran from the house (SRC).
  • He ran away from the house (SRC).
  • We drove from Pittsburgh (SRC) to Baltimore.
  • John left the house (SRC).
  • He heard the sound of liquid slurping in a metal container as Farrell approached him from behind. (Gildea - Source)
  • The teacher separated the boys from the girls (SRC).
  • We removed it from the room (SRC).

• Starting point of an exent:
  • The Ohio River runs from Pittsburgh (SRC) to the Mississippi.
  • The string stretched from the wall (SRC) to the door.

• Starting point of a change of state:
  • The liquid turned from red (SRC) to blue.

• Starting time:
  • The movie ran from 2:00 (SRC) to 4:00.

• Starting point of a change of possession:
  • We took the books from the students (SRC).
  • The thief robbed him (SRC) of him dignity (THM).

• Starting point of a communication:
  • We heard it from him (SRC).

SRC and AGT: In "We gave books to the students," "we" is the source of the change of possession, but it is also an agent. For now, label it as an agent.

SRC and GOL in commercial transactions and trades: In "We bought the books from the students for ten dollars" two things are exchanged, books and money. "The students" is the source of the books, but is the recipient of the money. Label it this way for now:

• We (AGT) bought books (THM) from the students (SRC) for ten dollars (POS).
• We (AGT) sold books (THM) to the students (GOL) for ten dollars (POS).

GOL: Goal

Basic Definition:

A goal is where something ends.

Examples:

• Ending point of a change of location:
  • He ran to school (GOL).
  • He ran home (GOL).
  • We drove from Pittsburgh (SRC) to Baltimore (GOL).
  • John arrived in Pittsburgh (GOL).
  • John reached Pittsburgh (GOL).

• Ending point of an exent:
  • The Ohio River runs from Pittsburgh (SRC) to the Mississippi (GOL).
  • The string stretched from the wall (SRC) to the door (GOL).

• Ending point of a change of state:
  • The liquid turned from red (SRC) to blue (GOL).
  • He became a teacher (GOL).
  • The carpenter hammered the nail (THM) flat (GOL).

• Ending time:
  • The movie ran from 2:00 (SRC) to 4:00 (GOL).

• Ending point of a change of possession (recipient):
  • We gave books (THM) to the students (GOL).
  • We gave the students (GOL) books.
  • We presented Lucy (GOL) with the award (THM).
  • We (GOL) received gifts.
  • We (GOL) got some gifts.

• Ending point of a communication:
  • We told the children (GOL) stories (THM).
  • We sang songs (THM) to the children (GOL).

• GOL and SRC in commercial transactions and trades: See notes under SRC.

• GOL and PRD: See notes under PRD.

• GOL and BEN: In "We gave the students books", the students are the recipients of books, and probably benefit from receiving the books. If we gave smallpox or poison to the students, they would still be recipients, but wouldn't benefit. So for now, if it is a recipient, label it as a GOL.
  • We gave books (THM) to the students (GOL).
  • I baked a cake (to give to Sam) for Sue (BEN).
  • I sang Sam (GOL) a song for Sue (BEN).