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Verbs, Part 4: Theta-Roles, or How to Eliminate Passive Voice

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My favorite syntax resource, Radford's English Syntax: An Introduction.
My favorite syntax resource, Radford’s English Syntax: An Introduction.

The discussion in this post requires a different view of language structure. For a deeper understanding, I refer you to Andrew Radford’s English Syntax: An Introduction (ISBN 0521542758), particularly pp. 190-193 . Much of this post draws from that source.


  1. Identify the theta-roles assigned to nouns by verbs.
  2. Revise Passive Voice from sentences by using verbs with alternate theta-role assignments.

Skill level: Advanced

Thematic Roles: An Overview

Thematic Roles, aka θ-roles or theta-roles (pronounced ‘THAY-ta’ or ‘THEE-ta’ if you’re an unenlightened mule-dodger), explain the different relationships between Verbs and Nouns in a sentence. For the purpose of this lesson we will regard these two constituents as follows:

  • Verbs = Events
  • Nouns = Participants

So. Picture a foot-race. There are runners, officials, and spectators. Each participates in the race but does so in a different manner: the runners run, the officials judge, and the spectators observe (and cheer or boo, as the case may be). Now, compare that event to a dental appointment, where you have participants, dentist and patient. The dentist examines or operates and the patient receives treatment. A footrace and a dental appointment are two distinctly different events with distinctly different types of participants. Agreed?

Well, if we consider every verb in the English language as an Event, we likewise discover different types of Participants. These are grouped together, just as one might group participants in a foot-race or at a dental appointment with broader categories of participants in any athletic competition or health-related appointment. The commonalities shared across Events produce a finite number of roles for the Participants to play. For grammatical Events, we categorize these Participants into theta-roles.

Radford defines seven theta-roles and their corresponding relationship to the Event (from Radford, Chapter 7, Item (14), found on p.190):

  1. Theme → Entity undergoing the effect of some action
  2. Agent → Entity instigating some action
  3. Experiencer → Entity experiencing some psychological state
  4. Locative → Place in which something is situated or takes place
  5. Goal → Entity representing the destination of some other entity
  6. Source → Entity from which something moves
  7. Instrument → Means used to perform some action

Numbers 4-7 often play ancillary roles to Numbers 1-3. We can easily associate them with prepositions (though they are not restricted to these prepositions alone, or to prepositional phrases exclusively):

  • Locative → “at”; The kids are playing at my house. (Note: My house is where the kids are playing.)
  • Goal → “to”; Lisa is going to the store. Myra gave a book to Brett. (Note: Brett received a book from Myra.)
  • Source → “from”; George drove here all the way from Buffalo. Brett received a book from Myra.
  • Instrument → “with”; Agnes hit Gregory with a paperweight.

Numbers 1-3, Theme, Agent, and Experiencer, typically play more central roles to the Event. We associate Agent and Experiencer with the subjects of transitive verbs; Theme is the object of a transitive verb, but it can also be the subject of some intransitive verbs. (Note: this is helpful to understand when studying ergative languages, such as Basque. We all secretly want to study Basque, right?) Examples:

  • Theme: The door shut. Mary shut the door.
  • Agent: Jack jumped over the candlestick.
  • Experiencer: Betty felt like throwing up.

If you give a hierarchy of power to these three theta-roles, the King of the Mountain is most definitely the Agent. The Agent acts, instigates, dominates.

I like to think of the Experiencer as a watered-down version of the Agent, that sidekick who looks on from the sidelines, and thus participates vicariously, as the action occurs. (As a side-note, “Experiencer” verbs tend to be the ones forbidden in all of those “Show, Don’t Tell” lectures that writers love to give one another; the Experiencer “tells” of an Event rather than acting in it.)

The Theme, then, is the object being acted upon, a position of little to no active power on its own, even as it undergoes change or receives attention from the Agent or Experiencer.

Thus, our proposed hierarchy of power goes Agent > Experiencer > Theme.

Theta-Roles and Voice

What’s any of this got to do with Passive Voice? Plainly put, Passive Voice ofttimes occurs when a writer or speaker removes the Agent/Experiencer from the subject position of the sentence (and sometimes from the sentence entirely). Passive Voice is weak because it removes the one who acts and replaces it with the Theme, the object acted upon, the weakest primary participant in the Event. (*Note: this evaluation of the Theme as “weak” applies only to its relationship with transitive verbs, when compared to that of the Agent or Experiencer. As a theta-role in general, it occupies a central and essential position to any narrative writing.)

So why might we be inclined to use Passive Voice?

  1. To minimize attention given to the Agent/Experiencer. E.g., a murder-mystery writer looking to draw out suspense doesn’t want to call attention to the murderer too early in the tale. Thus she might focus on the action that has been done rather than the actor who does it.
  2. To highlight the Theme as a focal point. The beginning of a sentence frames the reader’s focus. The subject becomes the center of attention. Thus, if a writer wants the reader to focus on a particular object or character being acted upon, he might use Passive Voice to frame that focus accordingly.

But here’s the thing: you can keep a Theme in the focus position without using Passive Voice. Compare the following:

  • The murder was committed on an otherwise peaceful Valentine’s Day.
  • The murder occurred on an otherwise peaceful Valentine’s Day.

In this example, both sentences are conveying the same information. Both have “the murder” as their subject/focus. The first uses Passive Voice, though, while the second uses Active Voice. The verb “to occur” is intransitive (just try putting it in a Passive Voice construct), and it happens to take a Theme as its subject.

And you know what else? You don’t even have to keep the Theme assignment on your noun/focus of choice. If you choose an active verb that converts your passive subject to an Agent instead, the narrative becomes that much more dynamic:

  • The murder was committed on an otherwise peaceful Valentine’s Day.
  • The murder shattered an otherwise peaceful Valentine’s Day.

I know which one I find more enthralling. Insert alternative active verbs (e.g., poisoned, tainted, enhanced), and you get a wide variety of possible tones for your narrative, all with the power of Active Voice behind them. (Doesn’t that sound like the tagline for a corny Saturday morning kids’ show? “By the Power of Active Voice, we fight!”)

By using a more dynamic verb, you’re adding an extra layer of information, too. “The murder enhanced an otherwise peaceful Valentine’s Day” doesn’t just tell you that it occurred; it also indicates that someone found value or pleasure in it. That “someone” might be a serial killer, a workaholic cop, or a member of the Addams Family. The use of “enhanced” effectively frames the narrative in any of those instances, where simple Passive Voice would fall short of the mark.

In other words, if you’re using too much Passive Voice in your writing, you need to find some new verbs.

And that brings us to this post’s handy PSA.

How to Eliminate Passive Voice (A Beginner’s Guide)

Method #1: Switch the sentence to Active Voice:

  • The candlestick was jumped over by Jack → Jack jumped over the candlestick.
    1. Pro: this puts the agent back in place. Your instigator is instigating again. Hooray for action!
    1. Con: this moves the focus of the sentence away from the object. Maybe you’re telling the story from the candlestick’s perspective. (You crazy nut.) Maybe you want to highlight the great (or not-so-great) obstacle Jack overcame in his jumping feat. But the reader is now focused on the agent, Jack, instead. Boo.

Method #2: Identify theta-roles and switch verbs accordingly:

  • The candlestick was jumped over by Jack → The candlestick proved no obstacle for Jack’s jumping skills.
    1. Pro: this maintains the original focus of the passive sentence while eliminating the weakness of Passive Voice.
    1. Con: this method requires some brainstorming to choose an appropriate verb without losing the intended meaning of the narrative. However, it also blows open the possibilities for how to frame the narrative, so maybe the brainstorming process is actually a Pro in disguise. Yay!

PLEASE NOTE: Passive Voice is not completely verboten. Used wisely, it can add to a narrative. Used too often, though, it gives a dry tone and erodes the strength of your narration. Nobody wants that. Don’t do it.


A. Identify the theta-roles of the bold words/phrases in the following paragraph.

I have told my reader in the preceding chapter that Mr. Allworthy inherited a large fortune, that he had a good heart, and no family. Hence, doubtless, it will be concluded by many that he lived like an honest man, owed no one a shilling, took nothing but what was his own, kept a good house, entertained his neighbors with a hearty welcome at his table, and was charitable to the poor, i.e., to those who had rather beg than work, by giving them the offals from it; that he died immensely rich, and built an hospital.

~Henry Fielding, Tom Jones, Chapter 3

[According to my calculations, the count is Theme (10), Agent (2), Experiencer (1), Locative (2), Goal (5), Source (1), and Instrument (1). There’s a reason that “Thematic Roles” are named in honor of the Theme. However, some theta-roles can seem a bit muddy to determine (which is why I did not bold the “he” in “that he lived like…” → it’s the subject of multiple verbs in a list and thus plays multiple theta-roles). If you end up with a different count, feel free to argue with me in the comments.]

B. Revise the Passive Voice from the following sentences by substituting an active verb (or verb phrase) that maintains the same subject and communicates a similar effect. (I’ll allow for some rephrasing in the predicates, if necessary. I’m magnanimous like that. )

  1. A cry was heard throughout the village.
  2. The picturesque meadow was currently occupied by a swarm of angry bees.
  3. A shoe was thrown at the president’s head.
  4. My lunch was smashed beneath the school bully’s dirt-encrusted sneakers.
  5. Her bicycle was stolen while she was in the store.
  6. The books were burned as the illiterate mob jeered in triumph.

2 thoughts on “Verbs, Part 4: Theta-Roles, or How to Eliminate Passive Voice”

    1. Thanks! I worry about being too dry with an already dry subject. Hopefully my “not thematic” voice helps in that department. 🙂

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