Pseudo-reflexivity
Alternating ambitransitives are not uncommon in English. In the Romance languages, such verbs are rarely found, since the same semantic concept is covered by pseudo-reflexive verbs. These verbs behave like ambitransitives, but the intransitive form requires a clitic pronoun that usually serves also for reflexive constructions. See for example, in Spanish (which uses the pronoun se in the third person):
- La ventana se rompió. "The window broke."
- Este barco se está hundiendo. "This boat is sinking."
- Se derritió todo el helado. "All of the ice cream melted."
In the example, the verbs romper, hundir and derretir are all transitive; they become intransitive by using the pseudo-reflexive clitic, and the direct object becomes the intransitive subject.
Ambiguity may arise between these and true reflexive forms, especially when the intransitive subject is animate (and therefore a possible agent). Me estoy hundiendo usually means "I'm sinking" (patientive first person), but it could also mean "I'm sinking myself", "I'm getting myself sunk" (agentive).
Read more about this topic: Ambitransitive Verb