Italian grammar

Italian grammar is the body of rules describing the properties of the Italian language. Italian words can be divided into the following lexical categories: articles, nouns, adjectives, pronouns, verbs, adverbs, prepositions, conjunctions, and interjections.

Articles

Italian articles vary according to definiteness, number, gender, and the initial sound of the subsequent word. Partitive articles compound the preposition di with the corresponding definite article, to express uncertain quantity. In the plural, they typically translate into English as 'few'; in the singular, typically as 'some'.

Gender	Number	Article	Usage
Masculine	Singular	il	Standard masculine singular definite article, used in all cases other than those detailed below. Foreign words beginning with, pronounced or, take il and not lo: il West , il whisky, il Watt, etc.
Masculine	Singular	lo	Used before words with certain initial sounds: before pronounced as,, or followed by another consonant before self-geminating consonants:, pronounced as or ; ; ; pronounced as before complex consonant clusters, pronounced as or ; as or ; as or, as or, etc., mostly foreign words before or pronounced as semivowel,
Masculine	Singular	l'	Used before words that begin with a vowel or .
Masculine	Plural	i	Standard masculine plural definite article, used for plurals that take il in the singular: i cani.
Masculine	Plural	gli	Corresponds to lo and l' in the singular: before vowels, pronounced /ʎ/ before the consonants listed for lo, pronounced /ʎi/ Il dio has the irregular plural gli dei.
Feminine	Singular	la	Standard form of the feminine singular definite article, used before consonants and before when pronounced as semivowel, e.g. la iarda.
Feminine	Singular	l'	As with l', used before any word that begins with a vowel, not including when pronounced as the semivowel.
Feminine	Plural	le	Standard form of the feminine plural definite article, never elided.

Gender	Article	Usage
Masculine	un	Standard masculine singular indefinite article, used before vowels and simple consonants.
Masculine	uno	Used instead of un before "impure s", self-geminating consonants, and complex consonant clusters, following the same rules as lo vs. il above, for example: uno studente.
Feminine	una	Standard feminine singular indefinite article.
Feminine	un'	Used before any word that starts with a vowel, not including when used as semivowel.

Gender	Number	Article	Contraction of
Masculine	Singular	del	di + il
Masculine	Singular	dell'	di + l
Masculine	Singular	dello	di + lo
Masculine	Plural	dei	di + i
Masculine	Plural	degli	di + gli
Feminine	Singular	della	di + la
Feminine	Singular	dell'	di + l
Feminine	Plural	delle	di + le

Inflection of nouns and adjectives

Nouns have gender and inflect in number. When a noun refers to people or animals with natural gender, grammatical gender typically corresponds. The gender each noun is written in is not arbitrary: because most nouns have a masculine and a feminine form, the form the given noun is written in could change the entire structure of the sentence. As in most other Romance languages, the historical neuter has merged with the masculine. A subgroup of these deriving from Latin's second declension are considered feminine in the plural. Subclauses and infinitives are masculine. Adjectives inflect for gender and number in patterns broadly similar to nouns.
In the last two examples, only the article carries information about gender and number.
Most masculine words that end in -io pronounced as drop the -o and thus end in -i in the plural: vecchio / vecchi, funzionario / funzionari, esempio / esempi, etc.
The Italian hard and soft C and G phenomenon leads to certain peculiarities in spelling and pronunciation:

Words in -cio and -gio form plurals in -ci and -gi, e.g. bacio / baci
Words in -cia and -gia have been a point of contention. According to a commonly employed rule, they:
* form plurals in -ce and -ge if the final letter before the suffix is a consonant: frangia, frange ; faccia, facce.
* form plurals in -cie and -gie if the final letter before the suffix is a vowel: camicia, camicie ; ciliegia, ciliegie. Note that the presence of an i in the plural ending has no impact on the pronunciation in this case.
* when the i is stressed, it always remains in plural: farmacia / farmacie, nevralgia / nevralgie.
Words in -co and -go behave irregularly: for some words the plural form causes the hard consonant to become soft, and for others the consonant remains hard. "The grammarians are skeptical of any attempt at giving a ruling about this area." There are, however, certain rules of thumb:
* plurals are formed with -chi and -ghi if the last letter before the suffix is a consonant or a stressed vowel: fungo / funghi, stecco / stecchi, mago / maghi, fuoco / fuochi
* plurals are formed with -ci and -gi if the last letter before the suffix is an unstressed vowel: comico / comici, medico / medici
* in words ending with -logo suffix, the plural is usually in -gi when -logo means 'expert' or 'student', corresponding to English -logist, while it is in -ghi when it means 'speech' or 'reasoning', corresponding often to English -logue/-log.
* there are exceptions such as amico / amici, greco / greci, valico / valichi, carico / carichi.
Words in -ca and -ga form plurals in -che and -ghe, e.g. amica / ami'che'''''
Nouns

Most nouns are derived from Latin. Many of these are themselves borrowed from Greek. Although Italian nouns do not inflect for case, they are derived from a mixture of the Latin nominative and accusative cases:

Latin declension	Italian singular/plural	Masculine	Feminine
1st	-a, -e		amica / amiche 'female friend'
1st & 2nd	-a, -i	poeta' / poeti 'poet'	ala'/ali 'wing'
2nd	-o, -i	amico' / amici 'friend'
3rd	-e, -i	cane' / cani 'dog'	parete' / pareti 'wall'
4th	-o, -i	passo' / passi 'step'	mano' / mani 'hand'
5th	-e, -i		fede' / fedi 'faith'

Nouns ending in any letter other than -a, -e or -o, as well as nouns ending in a stressed vowel, are normally invariable in the plural. Thus:

la gru / le gru
la città / le città
il caffè / i caffè
il film / i film

There are certain words that are masculine in the singular and feminine or masculine in the plural. Examples include:

il braccio / le braccia or i bracci
l'uovo / le uova
il ginocchio / le ginocchia or i ginocchi
il sopracciglio / le sopracciglia or i sopraccigli

These nouns' endings derive regularly from the Latin neuter endings of the second declension, but there are some from the third declension as well: e.g. il gregge / le greggi ; the tradition of calling them "irregular" or "mobile gender" would come from the paradigm that there are so few nouns of this type that the existence of neuter can be considered vestigial. The choice of plural is sometimes left to the user, while in some cases there are differences of meaning:

Sometimes, for body parts, the feminine/neuter plural denotes the literal meaning while the masculine one denotes a figurative meaning: il braccio / le braccia / i bracci ; il corno / le corna / i corni
Sometimes, especially in poetic and old-fashioned Italian, the masculine plural acts as a count noun, while the neuter/feminine plural acts as a mass noun: il cervello / due cervelli / le cervella ; l'anello / due anelli / le anella ; furthermore, il dito / le dita and also due dita / but i diti indici

Most noun stems are derived from the accusative: Latin socer/socerum begets Italian suocero, and Latin pēs/pēdem begets Italian piede. There are a few exceptions, however, such as uomo from Latin homo/hominem and moglie from Latin mulier/mulierem. Neuter third-declension nouns may bequeath Italian nouns either from the nominative/accusative case or from the oblique case used for other cases and for the plural.