In grammar, a future tense (abbreviated fut) is a verb form that marks the event described by the verb as not having happened yet, but expected to happen in the future (in an absolute tense system), or to happen subsequent to some other event, whether that is past, present, or future (in a relative tense system). The concept of the future, necessarily uncertain and at varying distances ahead, means that the speaker may express the future in terms of probability or intent ; the modality of intention is usually but not always present when a future construction is used.[1]:pp. 105-106 Whether future expression is realis or irrealis depends not on any objective, ontological notion of future reality, but rather on the speaker's conviction that the predicted event will at some future moment constitute reality.[2]:p.20 In many languages there is no morphological or syntactic indication of future tense. Future meaning is supplied by the context, with the use of temporal adverbs such as "later", or "next year", etc. Such adverbs (in particular words meaning "tomorrow" and "then") can also develop into grammaticalized future tense markers. In other languages, mostly languages of European origin, specific markers are used to indicate futurity. It is these structures which constitute the use of a "future tense." In many cases, an auxiliary verb is used. The auxiliary+verb sequence is typical of English, where "I will" or "I shall" is followed by the verb root. The auxiliary verb may also be combined with the verb root into a single word form, leading to reanalysis as a simple (one-word) future tense. This is in fact the origin of the future tense in Western Romance languages like Italian (see below). One significant deviation from this pattern, however, is to be found in Portuguese: in that language, a direct object may separate the root verb, and its syntactical marker for futurity ( as in, "eu dar-lhe-ei," "I will give it"). This process can also go in the other direction.[3] Thus, a given language may exhibit more than one strategy for expressing futurity. In addition, the verb forms used for the future tense can also be used to express other types of meaning. For example, "will", in English, may express direct volition as well as mark the future form of a verb. The auxiliary werden "become" is used for both the future tense and the passive voice in German. The formation of the future tense in English is less consistent than in some languages, and this has led some to argue that English does not have a future tense — that is, a grammatical form that, when used, always indicates futurity — nor does it have a form that is mandatory for the expression of futurity. However, there are several generally accepted ways of indicating futurity in English, and it is misleading to go from this inconsistency to assert that the tense does not exist.
<The most common auxiliary verbs used to express futurity are will and shall. Prescriptive grammarians distinguish between these, preferring to express the simple future as will in the second and third persons and shall in the first person, and preferring to express obligation or determination in the opposite cases. However, in modern English worldwide, shall and will are generally used interchangeably,[4] with will being more common. See also shall and will. Other periphrastic forms for the future include: to be going to + Verb, e.g. John is going to leave tonight. to be to + Verb, e.g. John is to leave tonight, which with the zero copula of newspaper headline style becomes simply to + Verb, e.g. John to leave tonight. A periphrastic form for the immediate future is to be about to + Verb, e.g. John is about to leave (any minute). A dialectical form in Northern England is: mun, derived from Old Norse, which implies obligation. In all dialects of spoken English both shall and will are commonly elided into 'll (I'll go could be either "I will go" or "I shall go") so that the differences between the two have been worn down. English also uses must, should, can, may and might in a similar way: Must expresses the highest degree of obligation and commitment (I / you must go) and is temporally nearest to present time in its expression of futurity ("I must go now.") Should (the subjunctive form of shall in this context) implies obligation or commitment to the action contemplated. Can implies the ability to commit the action but does not presuppose obligation or firm commitment to the action. May expresses a relatively low sense of commitment (I may go) and is the most permissive (You may go); it can also suggest conditionality (I may go [if I have time]). Might expresses a very low sense of commitment or obligation (I / you might go if I / you feel like it). English often employs the simple non-past (base form or base form + s in the third person singular) to convey scheduled futurity, as in tomorrow I leave at 5:00. The simple non-past form is mandatory for expressing the future in a dependent clause when the main clause uses will, shall, or (be) going to: I will see you when I get there (not ...when I will get there); If you build it they will come (not If you will build it...); she will not know that I am there (not ...that I will be there).