A verb () is a word (part of speech) that in syntax generally conveys an action (bring, read, walk, run, learn), an occurrence (happen, become), or a state of being (be, exist, stand). In the usual description of English, the basic form, with or without the particle to, is the infinitive. In many languages, verbs are inflected (modified in form) to encode tense, aspect, mood, and voice. A verb may also agree with the person, gender or number of some of its arguments, such as its subject, or object. Verbs have tenses: present, to indicate that an action is being carried out; past, to indicate that an action has been done; future, to indicate that an action will be done. For some examples: I washed the car yesterday. The dog ate my homework. John studies English and French. Lucy enjoys listening to music. Barack Obama became the President of the United States in 2009. (occurrence) Mike Trout is a center fielder. (state of being) Agreement In languages where the verb is inflected, it often agrees with its primary argument (the subject) in person, number or gender. With the exception of the verb to be, English shows distinctive agreements only in the third person singular, present tense form of verbs, which are marked by adding "-s" ( walks) or "-es" (fishes). The rest of the persons are not distinguished in the verb (I walk, you walk, they walk, etc.). Latin and the Romance languages inflect verbs for tense–aspect–mood (abbreviated 'TAM'), and they agree in person and number (but not in gender, as for example in Polish) with the subject. Japanese, like many languages with SOV word order, inflects verbs for tense-aspect-mood, as well as other categories such as negation, but shows absolutely no agreement with the subject—it is a strictly dependent-marking language. On the other hand, Basque, Georgian, and some other languages, have polypersonal agreement: the verb agrees with the subject, the direct object, and even the secondary object if present, a greater degree of head-marking than is found in most European languages. Types Verbs vary by type, and each type is determined by the kinds of words that accompany it and the relationship those words have with the verb itself. Classified by the number of their valency arguments, usually four basic types are distinguished: intransitives, transitives, ditransitives and double transitive verbs. Some verbs have special grammatical uses and hence complements,