syntaxis

in syntax, a verb, deriving from the Latin verbum meaning word, is a word (part of speech) that conveys action (bring, read, walk, run, murder), or a state of being (exist, stand). In most languages, verbs are inflected (modified in form) to encode tense, aspect, mood and voice. A verb may also agree with the person, gender, and/or number of some of its arguments, such as its subject, or object.

valency
he number of arguments that a verb takes is called its valency or valence. Verbs can be classified according to their valency:

* Intransitive (valency = 1): the verb only has a subject. For example: "he runs", "it falls".
* Transitive (valency = 2): the verb has a subject and a direct object. For example: "she eats fish", "we hunt nothing".

In English, it is impossible to have verbs with zero valency. Weather verbs are often impersonal (subjectless) in null-subject languages like Spanish, where the verb llueve means "It rains". In English, they require a dummy pronoun, and therefore formally have a valency of 1.[dubious – discuss]

The intransitive and transitive are typical, but the impersonal and objective are somewhat different from the norm. In this sense you can see that a verb is a person, place, thing, or link. In the objective the verb takes an object but no subject, the nonreferent subject in some uses may be marked in the verb by an incorporated dummy pronoun similar to the English weather verb (see below). Impersonal verbs take neither subject nor object, as with other null subject languages, but again the verb may show incorporated dummy pronouns despite the lack of subject and object phrases. Tlingit lacks a ditransitive, so the indirect object is described by a separate, extraposed clause.[citation needed]

English verbs are often flexible with regard to valency. A transitive verb can often drop its object and become intransitive; or an intransitive verb can take an object and become transitive.

In the first example, the verb move has no grammatical object. (In this case, there may be an object understood – the subject (I/myself). The verb is then possibly reflexive, rather than intransitive); in the second the subject and object are distinct. The verb has a different valency, but the form remains exactly the same.

In many languages other than English, such valency changes are not possible like this; the verb must instead be inflected in order to change the valency.[citation needed]