Theta Roles in English

[AureliaeLacrimae]

Words have meaning and function. According to their semantic function in the sentence, they also get a grammatical / syntactic function as well. There is one theory which bases everything on the verbs. The verb determines the complements and whether the sentence will have two objects, an object and a complement, just one object or nothing. 

 

The verb also carries certain semantic properties, which not only determine the number of complements, but also their type, i.e. form (whether to have a noun phrase or something else). Take for example put. Verb put in English asks for a direct object and location - put something somewhere, usually in the form of noun phrase (for direct object) and prepositional phrase (for location). So, a grammatical sentence with put can be:

I put the book on the table.

But certainly not *I put the book the table.

Although we have a direct object and potential location, it is not in the correct form, thus it cannot get the right thematic role.

 

When it comes to English, there are many thematic roles. It all depends on whether you're studying them from the point of view from generative or descriptive grammar. I prefer generative grammar and this is how it's usually described there:

 

Agent: the doer of an action, capable of volition; by virtue of his own volition achieves something;

Instrument: a tool with which an action is performed; used by an agent to achieve something; lacking independent volition;

Affected Object (Patient): the element undergoing the action or state;

Affected Object (Theme): the element undergoing a change of state involving location or movement;

Location: the place an action or state occurs;

Source: the starting point of a movement;

Goal: the end point of a movement;

Experiencer: the entity which is aware of the action or state described by the predicate but which is not in control of the action or state;

Beneficiary: the entity for whose benefit the action is performed;

Recipient: a special kind of goal found with verbs of possession, e.g. give;

Proposition: The thematic role assigned to clauses;    
 

 

Thus, in the previous sentence we have three arguments for the verb put: one subject and two complements.

I put the book on the table.

The subject "I" carries the theta role of Agent, because "I" is a subject capable of volition and is doing something.

The book gets the theta role of Theme, because it undergoes a change of state which involves either location or movement.

On the table is the Location.

 

Similar analysis can be applied to many other sentences. For example:

Mary cracked the nut with the hammer.

Mary is Agent (doing something), the nut gets the thematic (theta) role of Patient (no location or movement change) and with the hammer is Instrument.

 

The doctor examined the patient.

The doctor gets the thematic (theta) role of Agent (doing something) and the patient gets the thematic (theta) role of Patient (no change in location)

 

The postman brought the letter.

The postman  gets the thematic (theta) role of Agent and the letter is the theme (change of location).

 

 

There are also sentences where Agent is not the subject. For example.

The letter arrived.

The letter is theme. That's because the verb "arrive" is ergative and its subject begins as its complement.

 

The train is in the station.

The train gets the theta role of Theme and in the station that of Location.

 

The man felt .....

The man becomes Experiencer because of the verb "feel" which is not an action.