The matter of "é" vs. "è" is time-dependent and accent/region-dependent.
In the south of France, many occurences of "è" are changed to "é".
In the north, the difference is more marked, but the various ways of spelling do not necessarily map to a single pronunciation, although 'ai' does map to "è" in all cases I can think of.
This is not the case for "et" which, nowadays, is commonly pronounced "é" in the conjunction meaning "and" and can be pronounced "è" in other context (e.g. "un filet"). This has changed over time, and as far as I know there is no real rule besides usage...
(disclaimer: I'm a French native speaker from Savoie, without a marked local accent from this area) :)
Answer from gurney alex on Stack ExchangeAs a student in school, I have always considered ai/ais/ait to equal é. This has been what I at least think I've been hearing. I pronounce vrai as vré, J'ai as Jé, and J'étais would sound similar to J'ai été. And I can't recall ever being corrected on pronouncing ai/ais/ait as é.
I have recently purchased some books on French phonetics to help me with correct pronunciation. One book says the pronunciations used are those of Standard International French and Parisian French. All of them books say that ai as a verb ending is pronounced as é so that J'ai is Jé, Je donnai is Je donné, and Je donnerai is Je donneré. And that ai except as a verb ending is è. Je donnais is Je donnè, Je donnerais is Je donnerè, vrai and mais are vrè and mè.
I have also been pronouncing et and est both as é, but the books say that et is é and est is è.
I am not doubting that my book is the correct way of pronunciation, I am here to get a general idea of which is more widely used, which is more widely understood, and which is more formal.
Thank you for all of your advice and help, I will probably choose which pronunciation I stick with based which comes up as the most widely used pronounciation in the comments.
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The matter of "é" vs. "è" is time-dependent and accent/region-dependent.
In the south of France, many occurences of "è" are changed to "é".
In the north, the difference is more marked, but the various ways of spelling do not necessarily map to a single pronunciation, although 'ai' does map to "è" in all cases I can think of.
This is not the case for "et" which, nowadays, is commonly pronounced "é" in the conjunction meaning "and" and can be pronounced "è" in other context (e.g. "un filet"). This has changed over time, and as far as I know there is no real rule besides usage...
(disclaimer: I'm a French native speaker from Savoie, without a marked local accent from this area) :)
Both should not sound the same, but it is indeed often the case. As an example I will take what is probably the most common occurrence of words ending in -ai, the future tense:
Je serai à l'heure au rendez-vous
J'aurai des vêtements de rechange
In these cases, it should be pronounced a bit like "é", but indeed there's a tendency to pronounce it "è". While in most cases there is no ambiguïty (people will still understand this is the future), still it is not the correct pronunciation. I also think this induces spelling mistakes as you would be tempted to add an "s" in the end (if you pronounce it the same, why not write it the same after all)
I will compare with the same verbs in the conditional tense:
Je serais bien parti en vacances, mais je n'ai pas d'argent
J'aurais bien voulu partir en vacances
In these cases, it should indeed be pronounced "è", and usually it is.
In the other direction, words that should be pronounced "è" but are pronounced "é" (poulet, lait,...), the pronunciation is depending on the region where you are. On this, I can't refrain from thinking about this (well-known) advertising:
https://www.youtube.com/watch?v=2Mk-eag2IdE
Note: I'm a native from central Belgium and always lived there.