This comment is the oldest I have ever seen on Duo - as of 12 Feb 2018, the comment is 5 years old. I have seen many comments which are 4 years old, but this is the first 5 year old.
Anyway, one "rule" I follow in doing basic language study is to use cognates where they are valid and where I don't have a good reason to use a different word. This is one of those instances. "gone by" is certainly a valid translation, but "passed" and passato are just too close in spelling to avoid using them.
It's not a question of which is better, but whether you want to get more answer "right" for Duo. I know that Duo keeps track of these answers in figuring out your fluency, and maybe in determining whether you need to re-do modules. Getting the "right" answer saves times.
But in the case of passare there are both forms "ha passato" and "è passato": L’inverno è passato. Quarant'anni sono passati. (The winter has passed / is over. Forty years have passed / are over) // Io ho passato l'inverno / quarant'anni. (I have passed the winter / forty years). The difference is that in the first examples "passato" is used like an adjective, the winter or the years cannot actively do something, while in the second examples there is the "io" who is activly doing the passing. In more linguistic terms: In the first example the verb is intransitive and in the second it is transitive.
I like that idea of intransitive denoting how the verb relates to the subject of the sentence, while transitive verbs reflect some relationship with an object in the sentence (a thing or concept which is not the subject).
That's obviously not the definitive word on the subject of verbs, but it certainly is accurate and concise. Very helpful, because often I have a hard time figuring out whether a verb is being transitive or not. Many verbs can perform either function, depending on how they're used, so you can't just learn that a verb is transitive or intransitive, you have to figure out the function of the verb in context of the sentence.
After more studying, I found the following rules to decide wether to use "avere" or "essere". They are from a useful book on Italian conjugation called "I Verbe Italiani Regolari e Irregolari" by Angelo Chiuchiù ed al.
1) transitive verbs (direct object) require "avere"
2) reflexive verbs require "essere"
3) verbs in passive voice require "essere"
4) impersonal verbs which refer to atmospheric phenomena (piovere, nevicare, lampeggiare, ...) require "essere"
5) impersonal verbs which are only used in the 3rd person (succedere, occorrere, bastare, ...) require "essere"
6) many verbs which denote movement (avanzare, correrre, saltare, salire, ...) require "essere", when the action is seen as taking place in relation to an expressed or implied place (e.g. "Ho corso per tre ore" vs. "Sono corso alla stazione")
7) dovere, potere and volere take the auxiliary from the infinitive that follows ("Ho dovuto studiare molto" vs. "Sono dovuto uscire") 8) verbs that indicate a physical or mental change require "essere" (crescere, divenire, diventare, morire, ...)
9) verbs of place (accorrere, andare, arrivare, cadere, entrare, ...) require "essere"
Actually there is some structure: Verbs with "essere" are always intransitive (in Italian reflexive verbs also form the passato prossimo with "essere"), but alas not all intransitive verbs are with "essere". A second thing is that verbs which form the passato prossimo with "essere" (in French with "être", in German with "sein", etc.) always denote either a change of state (e.g. "diventare") or a change of location (e.g. venire) in one straight direction (A ---> B) or the lack thereof (e.g. "restare").
Because it isn't correct English. The word "are" refers to a state of being. You ARE in 2017, you ARE learning Italian. It is a present tense. Have (in this context) refers to something that the years had done (that is, passed), not what they are.
Now that said... obviously "sono" in Italian (from the Italian form of the question "Quarant'anni sono passati") is a form of the verb essere, which is "to be". That doesn't make either language more right or wrong than the other. It's just that with different languages, certain concepts are seen differently. Another example is "It is hot". In English being hot is a state of being. In Italian it's "fa caldo", literally, "it makes hot". In summary, you can't always translate literally because one language may see things differently from the other. The difference in how years passing is described is just another example of this.
If you learned that in school, then either you need a better school or the school needs to sack its teachers. They're probably the same ones who teach the words "nucular" and "foilage" (sic).
"Fourty" is not old fashioned, it is simply wrong. If you do a Google search with it you should see at the top of the results page "Showing results for Forty" You will not find the word "fourty" in any reputable dictionary. See, for example the Oxford. https://en.oxforddictionaries.com/search?filter=dictionary?query=fourty (You'll need to enter fourty into the search box; the link isn't automatically bringing up the results because Duo keeps stuffing around with and modifying the link that I entered when I posted this.)
The verb passare can take two conjugation forms - transitive or intransitive.
When using the transitive form, you combine the past participle of passare with the conjugated auxiliary verb avere.
When using the intransitive you combine the past participle of passare with the auxiliary verb essere. Both the past participle of passare and the auxiliary verb essere is conjugated to match gender and number.
Other verbs than passare may only have the transitive form, others have only the intransitive form and some, like passare have both. The use of which auxiliary verb to use to which form, depends on the main verb.
It depends on the sentence, which one of the forms you should use. In general, transitive verbs take an object, and intransitive verbs does not.
"Um", it has nothing to do with being American, which I'm not. (And if you're referring to my use of the Americanism "period" at the end - get over it. It's a common expression in both US and international English these days.) Go to the Oxford Dictionaries website and type in "fourty". This is where you end up: https://www.lexico.com/definition/forty
You do not go to a page with your incorrectly input "foUrty", but rather to a page with the correctly spelt FORTY.
Before you go around making strident declarations, try making sure that you have actual facts to back them up.
I have no idea what point you are trying to make (unless it's "I don't know how to spell", in which case you've made it with flying colours) but try these links: https://grammarist.com/spelling/forty-fourty/ https://www.grammarly.com/blog/forty-fourty/ https://writingexplained.org/forty-or-fourty-difference You writing several incorrectly spelt examples does not change this.