With a sentence like, "He sat on the couch," is sat still being used as an intransitive verb since, in general, prepositional phrases cannot act as direct objects? To me, the prepositional phase "on the couch" seems to be behaving like a direct object. If it is not behaving like a direct object, then I should not be able to construct a passive voice version of the sentence (i.e., "The couch was sat on by him"). To be sure, no one would actually use this passive voice construction, but it was nonetheless possible to create.

What am I misunderstanding here?

  • The passive voice is of course "The couch was sat on by me", though it sounds unnatural. And the verb sat as used in your sentence is of course intransitive.
    – user405662
    Jan 19, 2021 at 15:46
  • 3
    In other words, we can form a 'prepositional passive', "The couch was sat on" (using a short passive for greater naturalness).
    – BillJ
    Jan 19, 2021 at 16:03

1 Answer 1


In your example, "on the couch" is actually functioning as an adverbial phrase modifying "sat". It answers the question "where?"

If it were functioning as a direct object, your passive construction would be something like, "On the couch was sat by me," which is nonsensical. As it is, in the passive voice, the word "on" is in proximity to the verb it modifies, "sat".

  • 2
    Yes, the preposition on is being treated as a transitivizer, like into in That matter has been looked into. In effect, sit on is being treated like a transitive verb. Happens all the time; just an alternative parse. Jan 19, 2021 at 15:59
  • 1
    @Eric1982 If you have a lot of time, I'd recommend McCawley 1998. It's not an ESL text, though; it's intended to teach English syntax to native speakers. But it has all the information. It's just that it's a textbook for a 1-year college course in advanced English syntax, and while it's very clear and concise, it leaves in all the details and it's very very complicated. I'd compare it to a year's college course in vector analysis for difficulty. Jan 19, 2021 at 18:33
  • 2
    And that is why I feel intimidated every time I begin to answer a question and think, What would @JohnLawler say about this?
    – RobJarvis
    Jan 19, 2021 at 18:37
  • 1
    @RobJarvis What? You didn't like vector calculus? How about a year's course in mammalian evolution, with lab? Jan 19, 2021 at 18:39
  • 1
    "Sat" can be transitive, e.g. "I sat my baby on the floor," or "They sat the pot plant in the centre of the room." This use is infrequent. Jan 19, 2021 at 21:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.