It took me ages to find a reference that confirmed what was being said in response to Tom's question about agreement of the past participle for verbs conjugated with 'avere' when a direct object pronoun is used, so having done so - here it is:
Hope this helps
BajMaj : The past perfect tense is used to describe an action that took place in the past prior to some other more recently occurring past action. So usually you don't have just the one simple sentence by itself, as in this example, rather you have a compound sentence in which there are two past actions, one of which happened before the other. So: Where had you put it, when your parents asked about the alcohol? Ans: I'd (Ihad) already put it back in the liquor cabinet, before they even arrived home. In other words the tense is used when 2 past actions did not happen simultaneously. Here's another example: I was eating dinner, when you called. Both actions happened at the same time versus I had already eaten dinner when you called. You called at 8 pm and I'd eaten at 6. Or I had put the gun away when the cops arrived. They arrived at 8 and I'd (I had) put it away a half hour earlier. Etc. I hope this helps.
GermaineLee: No. When the direct object pronoun is present as here, then even those verbs which use 'avere' change their past participle to indicate the gender of that direct object pronoun. Since the past participle is 'messa' then the "it' referred to must refer to a feminine object. This is true for plural pronouns too.
Accepted or not, 'did put' and 'had put' are two different tenses, used differently. "Did put" could either express a 1 time action in the past: Where did you put the book this morning?" or depending on context, an habitual action in the past: "Where did you always put your book when you went to school as a child?" "Had put" expresses an action that had taken place before some other past action:" Where had you put the book, before I inquired about it?"
Why not "have put"? I don't really get the distinction between "have put" and "had put". I know that "have" would be used in passato prossimo so is the distinction something like: I have put it there (at some point in the recent past) or I had put it there (some time ago). It just doesn't seem like much of a distinction???
"Had put" describes a past action that happened prior to or before a more recently occurring past action. It's used when 2 past actions took place, one before the other. "You had already put the keys in the car (at 6 o'clock) , when I went to look for them (at 7 o'clock)." "You had already eaten, by the time I arrived." etc.
Bob: I'd probably answer that way too, if I were just answering the question: Have you eaten? Yes, I've already eaten. But if you're expressing TWO past actions in a single sentence, one of which happened before the other, than by right, one is past perfect tense, the other simple past. So: "Have you eaten?" "Yes, in fact I'd already eaten when you called." You wouldn't say: Yes, in fact I've already eaten when you called." Wouldn't that sound strange? I hope these help.