Catalan grammar

Catalan grammar, the morphology and syntax of the Catalan language, is similar to the grammar of most other Romance languages. Catalan is a relatively synthetic, fusional language.
Features include:
Some distinctive features of Catalan among Romance languages include the general lack of masculine markers (like Italian "-o"), a trait shared with French and Occitan; and the fact that the remote preterite tense of verbs is usually formed with a periphrasis consisting of the verb "to go" plus infinitive.
Articles.
Catalan has two types of article, definite and indefinite. They are declined for gender and number, and must agree with the noun they qualify. As with other Romance languages, Catalan articles are subject to complex elision and contraction processes.
The inflection of articles is complex, especially because of frequent elision, but is similar to neighboring languages. Catalan has more preposition–article contractions than Spanish, like "dels" ("of + the [plural]"), but fewer than Italian (which has "sul", "col", "nel", etc.).
Definite.
The tables below summarize the forms of the definite article, its elisions, and its contractions.
Articles for personal names.
Forenames and surnames must carry a definite article. In addition to the ordinary singular forms, alternative forms derived from the Latin vocative "domine" can be used. The elision rules are the same for "el" and "la".
Dialectal variation.
In Western Catalonia the dialectal versions "lo" and "los" are used instead of "el" and "els".
In some regions, especially in the Balearic islands, the definite article derives from the Latin determiner "ipse". These forms are referred to as "articles salats". Similar forms are found in Sardinian and some varieties of Occitan.
Indefinite.
The table below summarize the forms of the indefinite article. Indefinite articles are not elided nor contracted.
Overview of gender and number inflection.
Most adjectives, and a fair number of nouns, inflect for gender. This usually follows a regular pattern of endings. The two main patterns are generally referred to as "four-form" and "two-form" adjectives. Four-form adjectives have distinct masculine and feminine forms, whereas two-form adjectives have the same form for both masculine and feminine. They are derived from the Latin first/second, and the third declension respectively. Many nouns follow the four-form inflection, but some may follow the two-form inflection. Some are irregular in some way.
Similar to French, but unlike Portuguese, Spanish or Italian, the Latin/Romance final "-o" and "-e" have disappeared. Thus, the alternance of "-o"/"-a" in the four-form words has been substituted by "-"/"-a". There are only a few exceptions, like "minso"/"minsa" ("scarce").
Among nouns, Catalan has few suppletive couplets, like Italian and Spanish, and unlike French. Thus, Catalan has "noi"/"noia" ("boy"/"girl") and "gall"/"gallina" ("cock"/"chicken"), whereas French has "garçon"/"fille" and "coq"/"poule". 
There is a tendency to inflect adjectives as four-form instead of two-form, something that is prevalent in Occitan and standard in French. Thus, alongside traditional two-form "bullent"/"bullent" ("boiling"), one can also find four-form "bullent"/"bullenta".
Variants.
Many not completely predictable morphological alternations may occur between masculine and feminine, like:
In words that end in a sibilant sound, the masculine plural ending is "-os" instead of just "-s". Feminines still have "-es" or, if they follow the two-form declension, no ending at all. Compare: "el pols"/"els polsos" ("the pulse"/"the pulses") vs. "la pols"/"les pols" ("the dust"/"the dusts").
Adjectives that end in "-ç" follow the two-form declension in the singular, but four-form in the plural, so that they actually have three forms:
Nouns.
Catalan nouns are inflected for gender (masculine or feminine), and number (singular or plural). There is no case inflection. Articles and adjectives agree in gender and number with the noun they refer to.
Usually, masculine nouns are unmarked, feminine nouns carry the suffix "-a"; and the plural is marked with the suffix "-s", which makes the feminine ending turn into "-e-". Thus, the most common declension paradigm for Catalan names is the one that follows:
Gender inflection.
The grammatical gender of a Catalan noun does not necessarily correspond with the real-life object's biological sex (or lack thereof). Nouns denoting a person, such as "home" "man" or "dona" "woman", generally agree with the natural gender of what is described. However, Catalan assigns gender to nouns without natural gender in arbitrary fashion. For example, the word "tamboret" ("stool") is masculine, while the word "cadira" ("chair") is feminine.
Living beings with distinct masculine and feminine forms.
Living beings of the same species usually are designed by two nouns: one of masculine grammatical gender for biologically male individuals, and one of feminine grammatical gender for biologically female individuals. Both names, masculine and feminine, are usually only differentiated by their ending; sometimes the second is derived from the first or vice versa. Rarely, both come from different roots.
Number inflection.
Like all the Western Romance languages, the formation of the plural involves the addition of the suffix "-s" to the singular. However, the stem may undergo some changes. The number inflection of adjectives follows the same rules.
Adjectives.
A Catalan adjective must agree in gender and number with the noun it accompanies. Most adjectives are placed after the nouns. Adjectives can be divided into three declension paradigms. The number inflection rules are the same as the nouns.
Declension.
Catalan adjectives can be divided in three groups according to the distinct forms it has.
Formation of the feminine singular from the masculine singular.
In adjectives with distinct feminine singular form, the masculine is usually unmarked for gender, and ends in a consonant. The feminine singular form of regular adjectives can be created from the masculine singular.
Marked masculine forms ending in "-e" or "-o".
If the masculine form ends in "-e" or "-o", the final vowel is substituted with "-a". Many of the adjectives ending in "-o" come from Spanish. 
Adjectives with indistinct masculine and feminine forms.
Some adjectives may have the same form in the masculine singular and feminine singular.
Irregular feminine forms.
Some feminine adjectives are formed irregularly and do not adhere to the aforementioned formation rules.
Degrees of comparison.
Degrees of comparison are expressed with a construction implying the adverb "més" "more" or "menys" "less":
Absolute superlative.
Like many other Romance languages, Catalan adjectives have an absolute superlative form, expressed with the suffix "-íssim", placed between the stem and the gender / number suffix.
Adverbs.
Catalan adverbs, like their English counterparts, are used to modify adjectives, other adverbs, and verbs or clauses. They do not display any inflection; that is, their form does not change to reflect their precise role, nor any characteristics of what they modify.
Formation.
In Catalan, as in English, most adverbs are derived from adjectives. In most cases, this is done by adding the suffix "-ment" ("-ly") to the adjective's feminine singular form. For example, the feminine singular form of "lent" ("slow") is "lenta", so the corresponding adverb is "lentament" ("slowly").
As in English, however, the adjective stem is sometimes modified to accommodate the suffix:
And, as in English, many common adverbs are not derived from adjectives at all:
Placement.
The placement of Catalan adverbs is almost the same as the placement of English adverbs.
An adverb that modifies an adjective or adverb comes before that adjective or adverb:
An adverb that modifies an infinitive (verbal noun) generally comes after the infinitive:
An adverb that modifies a main verb or clause comes either after the verb, or before the clause:
Note that, unlike in English, this is true even of negative adverbs:
Possessives.
Possessive pronouns.
Possessive adjectives are inflected for person and number of the possessor, and for gender and number of the possession.
The table below summarizes all the possible forms.
The feminine forms "meva", "teva", and "seva" may appear dialectally with instead of : "meua", "teua", and "seua". Their plural forms follow the same variation ("meues", "teues", and "seues").
Possessive adjectives.
Possessive adjectives are, like the possessive pronouns, inflected for person and number of the possessor, and for gender and number of the possession. The table below summarizes all the possible forms. Notice how the plural possessor forms are identical to the possessive pronoun forms.
Central Catalan has abandoned almost completely unstressed possessives ("mon", etc.) in favour of constructions of article + stressed forms ("el meu", etc.), a feature shared with Italian and Portuguese.
Pronouns.
Personal pronouns.
The morphology of Catalan personal pronouns is complex, specially in unstressed forms, which are numerous (13 distinct forms, compared to 11 in Spanish or 9 in Italian; French has such a different system that comparisons are not feasible). Features include the neuter gender ("ho") and the great degree of freedom when combining different unstressed pronouns (65 combinations).
This flexibility allows Catalan to use extraposition extensively, much more than French or Spanish. Thus, Catalan can have "m'hi recomanaren" ("they recommendedd me to him"), whereas in French one must say "ils m'ont recommendé à lui", and in Spanish "me recomendaron a él". This allows the placement of almost any nominal term as a sentence topic, without having to use so often the passive voice (as in French or English), or identifying the direct object with a preposition (as in Spanish).
Verbs.
Catalan verbs express an action or a state of being of a given subject, and like verbs in most of the Indo-European languages, Catalan verbs undergo inflection according to the following categories:
Like all the Romance languages, Catalan verbal inflection is more complex than the nominal. Suffixation is omnipresent, while morphological alternations play a secondary role. Vowel alternances are active, as well as infixation and suppletion. However, these are not as productive as in Spanish, and are mostly restricted to irregular verbs.
The Catalan verbal system is basically common to all Western Romance, except that most dialects replace the analytic perfect indicative with a periphrastic tense composed of "vaig, vas (vares), va, vam (vàrem), vau (vàreu), van (varen)" and the infinitive.
Catalan verbs are traditionally divided into three conjugations, with vowel themes "-a-", "-e-", "-i-", the last two being split into two subtypes. However, this division is mostly theoretical. Only the first conjugation is nowadays productive (with about 3500 common verbs), while the third (the subtype of "servir", with about 700 common verbs) is semiproductive. The verbs of the second conjugation are fewer than 100, and it is not possible to create new ones, except by compounding.
Verbal periphrases.
Verbal periphrases of obligation:
(*) Although it is not correct the usage of the verbal periphrasis *"tenir" + "que" + infinitive (obligation) in the Standard (instead of "haver" + "de", which is roughly equivalent to English "have to"), it is widely used in colloquial Catalan and Valencian. The same occurs with *"haver-hi" + "que" + infinitive.
Verbal periphrases of probability:
Verbal periphrases of imminence, intention or future: 
Other modal and aspectual verbal periphrases: