Spanish object pronouns
Spanish object pronouns are Spanish personal pronouns that take the function of the object in the sentence. Object pronouns may be both clitic and non-clitic, with non-clitic forms carrying greater emphasis. When used as clitics, object pronouns are generally proclitic, i.e. they appear before the verb of which they are the object; enclitic pronouns (i.e. pronouns attached to the end of the verb) appear with positive imperatives, infinitives, and gerunds. Non-clitic forms, by contrast, can appear anywhere in the sentence but can rarely be used without their clitic counterparts. When used together, clitic pronouns  cluster in specific orders based primarily on person, and clitic doubling is often found as well. In many dialects in Central Spain, including that of Madrid, there exists the phenomenon of "leísmo", which is using the indirect object pronoun "le" as the direct object pronoun where most other dialects would use "lo" (masculine) or "la" (feminine). History. As the history of the Spanish language saw the shedding of Latin declensions, only the subject and prepositional object survived as independent personal pronouns in Spanish: the rest became clitics. These clitics may be proclitic or enclitic, or doubled for emphasis. In modern  Spanish, the placement of clitic pronouns is determined morphologically by the form of the verb. Clitics precede most conjugated verbs but come after infinitives, gerunds, and positive imperatives. For example: me vio" but "verme, "viéndome", "¡véame!" Exceptions exist for certain idiomatic expressions, like "once upon a time" ("Érase una vez"). Old Spanish. Unstressed pronouns in Old Spanish were governed by rules different from those in modern Spanish. The old rules were more determined by syntax than by morphology: the pronoun followed the verb, except when the verb was preceded (in the same clause) by a stressed word, such as a  noun, adverb, or stressed pronoun. For example, from " Cantar de Mio Cid": If the first stressed word of a clause was in the future or conditional tense, or if it was a compound verb made up of "haber" + a participle, then any unstressed pronoun was placed between the two elements of the compound verb. Before the 15th century, clitics never appeared in the initial position; not even after a coordinating conjunction or a caesura. They could, however, precede a conjugated verb if there was a negative or adverbial marker. For example: The same rule applied to gerunds, infinitives, and  imperatives. The forms of the future and the conditional functioned like any other verb conjugated with respect to the clitics. But a clitic following a future or conditional was usually placed between the infinitive root and the inflection. For example: Early Modern Spanish. By the 15th century, Early Modern Spanish had developed "proclisis", in which an object's agreement markers come before the verb. According to Andrés Enrique-Arias, this shift helped speed up language processing of complex morphological material in the verb's inflection (including time, manner, and aspect). This proclisis ("ascenso de clítico") was a syntactic movement away  from the idea that an object must follow the verb. For example, in these two sentences with the same meaning: "Lo" is the object of "comprar" in the first example, but Spanish allows that clitic to appear in a preverbal position of a syntagma that it dominates strictly, as in the second example. This movement only happens in conjugated verbs. But a special case occurs for the imperative, where we see the postverbal position of the clitic This is accounted for by a second syntactic movement wherein the verb "passes by" the clitic that has already "ascended". Usage. Spanish object  pronouns come in two forms: clitic and non-clitic, or stressed. Clitics, by definition, cannot function independently, and they therefore must appear attached to a host (a verb or preposition). With verbs, clitics may appear as proclitics before the verb or as enclitics attached to the end of the verb, with proclitization being significantly more common. When used together, clitic pronouns cluster in specific orders, and the process of enclitization is subject to certain rules in which sounds are dropped. Non-clitic pronouns, by contrast, are the stressed form of object pronouns; they are formed with the preposition "a  (to") and the prepositional case of the pronoun. In contrast to clitic pronouns, non-clitic pronouns can appear anywhere in the sentence, but with very few exceptions, they cannot be used without their clitic counterparts (a process known as clitic doubling). When used as clitics, object pronouns are generally proclitic, i.e. they appear before the verb of which they are the object. Thus: In certain environments, however, enclitic pronouns (i.e. pronouns attached to the end of the verb or a word derived from a verb) may appear. Enclitization is generally only found with: With positive imperatives, enclitization is always  mandatory: With negative imperatives, however, proclitization is mandatory: With infinitives and gerunds, enclitization is often, but not always, mandatory. With bare infinitives, enclitization is mandatory: In compound infinitives that make use of the past participle (i.e. all perfect and passive infinitives), enclitics attach to the uninflected auxiliary verb and not the past participle itself: In compound infinitives that make use of the gerund, however, enclitics may attach to either the gerund itself or the main verb, including the rare cases when the gerund is used together with the past participle in a single infinitive: With bare gerunds, enclitization is once  again mandatory. In compound gerunds, enclitics attach to the same word as they would in the infinitive, and one has the same options with combinations of gerunds as with gerunds used in infinitives: In constructions that make use of infinitives or gerunds as arguments of a conjugated verb, clitic pronouns may appear as proclitics before the verb (as in most verbal constructions) or simply as enclitics attached to the infinitive or gerund itself. Similarly, in combinations of infinitives, enclitics may attach to any one infinitive: Enclitics may be found in other environments in literary and archaic language, but such constructions  are virtually absent from everyday speech. Enclitization is subject to the following rules: Non-clitic, or stressed pronouns, on the other hand, do not require a host, and they can thus be placed anywhere in the sentence. With very few exceptions, however, they must be used along with their clitic equivalents: Non-clitic accusative pronouns cannot have impersonal antecedents; impersonal accusative clitics must therefore be used with their antecedents instead: Impersonal dative clitic pronouns, however, may be stressed as such: In a similar vein, impersonal accusative clitics are occasionally used to provide a degree of emphasis to the sentence  as a whole: Combinations of clitic pronouns. In Spanish, up to two (and rarely three) clitic pronouns can be used with a single verb, generally one accusative and one dative. Whether enclitic or proclitic, they cluster in the following order: Thus: When an accusative third-person non-reflexive pronoun ("lo", "la", "los", or "las") is used with a dative pronoun that is understood to also be third-person non-reflexive ("le" or "les"), the dative pronoun is replaced by "se": If "se" is being used as a reflexive indirect object, however, it is often, though not always, disambiguated with "a  sí": Only one accusative clitic can be used with a single verb, and the same is true for any one type of dative clitic as well as prepositional clitics. When more than one accusative clitic, dative clitic of a specific type, or prepositional clitic is used, therefore, the verb or preposition must be repeated for each clitic used: Occasionally, however, with verbs such as "dejar" ("to let"), which generally takes a direct object as well as a subsequent verb as a further grammatical argument, objects of two different verbs will appear together and thus may appear to be objects of  the same verb: Like Latin, Spanish makes use of double dative constructions, and thus up to two dative clitics can be used with a single verb. One must be the dative of benefit (i.e. someone (or something) who is indirectly affected by the action), and the other must refer to the direct recipient of the action itself. Context is generally sufficient to determine which is which: Clitic doubling. In addition to providing emphasis, clitic doubling often occurs for purely grammatical reasons, most often with dative clitics but sometimes with accusative clitics as well. All non-clitic indirect objects as well  as the majority of personal non-clitic direct objects must be preceded by the preposition "a", and an appropriate dative clitic pronoun is thus often used to distinguish between them. With indirect objects that come before the verb, clitic doubling is mandatory in the active voice: With indirect objects that come after the verb, however, clitic doubling is usually optional, though generally preferred in spoken language: Nevertheless, with indirect objects that do not refer to the direct recipient of the action itself as well as the dative of inalienable possession, clitic doubling is most often mandatory: With indefinite pronouns, however , clitic doubling is optional even in such constructions: In the passive voice, where direct objects do not exist at all, non-emphatic dative clitic doubling is always optional, even with personal pronouns: Non-emphatic clitic doubling with accusative clitics is much rarer. It is generally only found with: Thus: Accusative clitic doubling is also used in object-verb-subject (OVS) word order to signal topicalization. The appropriate direct object pronoun is placed between the direct object and the verb, and thus in the sentence "La carne la come el perro" ("The dog eats the meat") there is no confusion about  which is the subject of the sentence ("el perro"). Clitic doubling is often necessary to modify clitic pronouns, whether accusative or dative. The non-clitic form of the accusative is usually identical to that of the dative, although non-clitic accusative pronouns cannot be used to refer to impersonal things such as animals and inanimate objects. With attributive adjectives, nouns used with apposition (such as "us friends"), and the intensifier "mismo", clitic doubling is mandatory, and the non-clitic form of the pronoun is used: With predicative adjectives, however, clitic doubling is not necessary. Clitic pronouns may be directly  modified by such adjectives, which must be placed immediately after the verb (or related word): Prepositional and comitative cases. The prepositional case is used with the majority of prepositions: "a mí", "contra ti", "bajo él", etc., although several prepositions, such as "entre" ("between, among") and "según" ("according to"), actually govern the nominative (or "sí" in the case of "se"): "entre yo y mi hermano" ("between me and my brother"), "según tú ("according to you"), "entre sí ("among themselves"), etc., with the exception of "entre nos" ("between us"), where the accusative may be used instead ("entre nosotros" is also acceptable). With  the preposition "con" ("with"), however, the comitative is used instead. "Yo", "tú", and "se" have distinct forms in the comitative: "conmigo", "contigo", and "consigo", respectively, in which the preposition becomes one word with its object and thus must not be repeated by itself: "conmigo" by itself means "with me", and "con conmigo" is redundant. For all other pronouns, the comitative is identical to the prepositional and is used in the same way: "con él", "con nosotros", "con ellos", etc. As with verbs, prepositions must be repeated for each pronoun they modify: