Past participle and changing endings with auxiliary verb "avere"


I have read many times that the endings of the past participle doesn't change when used in conjunction with the auxiliary verb "avere". However I am increasingly noticing that is is not the case. For example I recently came across:

Li ho messi in tasca

Maybe this particular example is wrong or colloquial, I don't know, but I've seen it enough times to make me think this is acceptable. However, I can't find any reference to this in any of my textbooks, nor online. Can anyone help?


Posted 2013-11-06T16:03:02.810

Reputation: 443



With a pronoun as object, the only allowed form is the one you used: nobody would say "*Li ho messo in tasca". With an explicit object, the participle is invariable: "Ho messo i libri in tasca".


Posted 2013-11-06T16:03:02.810

Reputation: 2 115

2Thanks. Simple. I don't know how I've overlooked this for so long.Groky 2013-11-06T16:16:39.933

‘Ho messi i libri in tasca’ is allowed, but not much used nowadays.egreg 2013-11-06T16:51:14.187


Past participles definitely do change according to the object gender and number for transitive verbs when the object is a pronoun, like in your example. They do not, however, change if the verb is intransitive, even if its passato prossimo uses “avere”, like “ho pranzato”.

(some examples, as requested in comments)

Transitive verbs - singular subject

  • Ho visto una casa — singular explicit object (una casa). Base participle form.
  • Ho visto due case — plural explicit object (due case). Base participle form.
  • L'ho vista — singular pronoun as object (la). Participle gains the pronoun gender.
  • Le ho viste — plural pronoun as object (le). Participle gains the pronoun gender & number.

Transitive verbs - plural subject

  • Abbiamo visto una casa
  • Abbiamo visto due case
  • L'abbiamo vista
  • Le abbiamo viste

No effect on participle.

Intransitive verbs

  • Ho pranzato
  • Abbiamo pranzato
  • Claudia ha pranzato

Again, no effect on participle.

Tricky cases

  • Le ho detto — Le is not the object, but complemento di termine.


Posted 2013-11-06T16:03:02.810

Reputation: 731

2I like this answer, but I'd love to see it improved. In particular, you could provide examples of the different categories. I'd be particularly interested in "Ho visto Claudia"/"L'ho vistA", for instance.martina 2013-11-14T21:30:52.077

@martina good call. I added some examples.Agos 2013-11-19T21:36:16.060


The past participle used with avere and the passato prossimo as tense doesn't change basing on the gender and the plurality. You say ho messo a posto il frullatore and ho messo a posto i temperini nel cassetto.

Since there is li, the past participle is declinated basing on the plurality of the object.


Posted 2013-11-06T16:03:02.810

Reputation: 2 570