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Stress placement in Italian is variable, just like in English (the stressed syllable changes from word to word). However, Italian has somewhat firmer rules for stress placement than English, and, unlike English, there are cases where stress has to be indicated with diacritical marks (or “accents”).
Grave accent
There two kinds of accents in Italian. The most common one by far is the so called accento grave (or “grave accent” in English, usually pronounced /ɡrɑːv/), which is a little line pointing downwards and can appear above any vowel, e.g.
città – city
è – is
morì – he/she died
falò – bonfire
Perù – Peru
(notice that it replaces the dot in “i”). It is obligatory to use the grave accent in the following cases:
1) In polysyllabic words (words that have more than one syllable) in which the final syllable is stressed, such as città, falò, or Perù. Note that in certain cases, the acute accent (which we will talk about later) appears above the letter “e” instead.
2) In monosyllabic words of the form “consonant + i or u + vowel”, namely chiù (horned owl), ciò (this, that), già (yet, already), giù (down), piè (footer), più (more), può (he can), scià (shah, a Persian ruler). The words qua and qui (both meaning “here”) are written without any accent, because the “u” is part of the digraph “qu”.
3) In a few monosyllabic words to distinguish two different meanings of the word:
da – from or since; dà – he/she gives
di – of, from; dì – day, as opposed to night
e – and; è – he/she/it is
la – the; là – there
si – itself, herself, himself; sì – yes
Again, in certain cases, explained later, the acute accent is used instead.
In some cases, a word can have two possible pronunciations with different stress positions, with the two pronunciations expressing two completely different things. For example, the word principi changes its meaning depending on word the first are the second syllable is stressed:
principi (PREEN-chee-pee) = plural of principe, “prince”,
principi (preen-CHEE-pee) = plural of principio, “beginning” or “principle”.
When this happens, it is possible to indicate the stress position with the grave accent, but this is uncommon outside the context of dictionaries and language instruction. For example, “Harry and William are princes in Great Britain” could be translated as
Harry e William sono principi in Gran Bretagna. (most common)
Harry e William sono prìncipi in Gran Bretagna. (possible)
It would be incorrect to write “Harry e William sono princìpi in Gran Bretagna”, since “princìpi” does not mean “princes”.
Here are a few other examples of words that change their meaning depending on stress position (again, as noted above, the accents are usually not written, but they may be used in certain contexts to make the intended pronunciation clear):
àncora – anchor; ancòra – again, another time
nòcciolo – fruit stone (kernel); nocciòlo – hazel
sùbito – immediately; subìto – endured
There are even words with three possible stress positions, for example spìano = they spy, spiàno = I level; spianò = he/she levelled. The first two would not usually have a written accent, but the accent is obligatory in the last one, since it is located on the last syllable.
Acute accent
The acute accent is a small upwards-pointing line, sometimes used also in English in words like “café” and “fiancée” (which, however, come from French, not Italian). In Italian, the acute accent is normally used only in connection with the letter “e” (and possibly with the letter “o”, as we will see below). The vowel “e” in stressed syllables has two possible pronunciations in Italian: a close one, with the tongue close to the soft palate, and an open one, which is the same as “e” in the English word “bet”.
The grave accent (“è”) customarily indicates the open pronunciation, so to distinguish words with the close e, the acute accent (“é”) is used instead. Most importantly, words ending with -ché have an acute accent above “e”, e.g. perché (why), poiché (since, because), affinché (in order that), as well as numbers ending with -tré, e.g.
ventitré (twenty-three).
It is also used in a few monosyllabic words to distinguish two different meanings (and pronunciations), e.g. né (neither, nor) as opposed to ne (“from there” or “of it”) and sé (oneself, himself, herself) as opposed to se (“if”).
Just like the grave accent, the acute accent is normally not used when the stressed syllable is any other than the last one. It may be used in dictionaries and in language instruction to help learners remember the correct pronunciation, but in practice, you will have to learn whether an “e” is in fact “é” or “è” by heart.
It is worth noting that “é” is the least common letter of the Italian alphabet, so you shouldn’t worry too much about general rules governing its usage; it is better to simply memorize the few words that contain it.
Strictly speaking, an even less common letter of the Italian alphabet is “ó”, which, just like “é”, indicates the close pronunciation of the letter “o”, but since this pronunciation does not appear at the end of words, you will pretty much never see it in practice, except in dictionaries.
Stress patterns
The stress in Italian is variable, but it is often possible to guess its position even when it is not marked with diacritics. First a bit of practical advice: If you have no idea where to pronounce the stress in a certain word, put it on the penultimate (second-to-last) syllable. Most words in Italian are stressed on the penultimate syllable, so, statistically speaking, this will increase your chances of pronouncing the word correctly (of course, if you have time to check the correct pronunciation in a dictionary, that’s better than any guesswork).
The advice above should be combined with the following piece of information. Just like we know that it is the third-to-last syllable that is stressed in English words ending with -logical, such as geological, physiological, and psychological, there are certain suffixes in Italian that make the word stressed on the third-to-last syllable. These are:
-agine, -aggine, -igine, -iggine, -edine, -udine, -abile, -evole, -ibile, -ico, -aceo, -ognolo, -oide, -cefalo, -crate, -dromo, -fago, -filo, -fobo, -fono, -gamo, -geno, -gono, -grafo, -logo, -mane, -metro, -nomo, -stato, -tesi, -ttero, -fero, -fugo, -voro
To apply the rule correctly, you have to be sure that the group of letters described above is a real suffix; for example, the -voro suffix corresponds to English -vore, as in carnivoro, but it is not a suffix in lavoro, meaning “work”, which is stressed on “vo”.
