Future tense in the context of Relative tense

A verb is a word that 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. In English, three tenses exist: present, to indicate that an action is being carried out; past, to indicate that an action has been done; and future, to indicate that an action will be done, expressed with the auxiliary verb will or shall.

In grammar, tense is a category that expresses time reference. Tenses are usually manifested by the use of specific forms of verbs, particularly in their conjugation patterns.

The main tenses found in many languages include the past, present, and future. Some languages have only two distinct tenses, such as past and nonpast, or future and nonfuture, while some languages make finer tense distinctions, such as remote vs recent past, or near vs remote future. There are also tenseless languages, like most of the Chinese languages, however, these languages do refer to time in different ways.

The present tense (abbreviated PRES or PRS) is a grammatical tense whose principal function is to locate a situation or event in the present time. The present tense is used for actions which are happening now. In order to explain and understand present tense, it is useful to imagine time as a line on which the past tense, the present and the future tense are positioned. The term present tense is usually used in descriptions of specific languages to refer to a particular grammatical form or set of forms; these may have a variety of uses, not all of which will necessarily refer to present time. For example, in the English sentence "My train leaves tomorrow morning", the verb form leaves is said to be in the present tense, even though in this particular context it refers to an event in future time. Similarly, in the historical present, the present tense is used to narrate events that occurred in the past.

There are two common types of present tense form in most Indo-European languages: the present indicative (the combination of present tense and indicative mood) and the present subjunctive (the combination of present tense and subjunctive mood). In English, the present tense is mainly classified into four parts or subtenses.

The nonpast tense (also spelled non-past) (abbreviated NPST) is a grammatical tense that distinguishes an action as taking place in times present or future. The nonpast tense contrasts with the past tense, which distinguishes an action as taking place prior to the moment of utterance.

The nonpast tense is observed in many languages. Due to a lack of future tense inflectional morphology on the verb stem, many languages that are popularly conceived as having a three-way tense distinction (between past, present, and future), can in fact be understood as having a two-way past-nonpast tense distinction. For example, in English, future sentences often take present tense verb morphology, and do not contain specialized future tense verb morphology. In contrast, past tense sentences require specialized past tense morphology. Compares for instance the sentence: I hope he gets [nonpast] better tomorrow (in which the main verb gets is conjugated in the present tense, and the future is indicated lexically through the word tomorrow), and the sentence I hope he got [past] better yesterday (which requires the use of a specialized past tense form, got, for the main verb; use of gets is ungrammatical).

A nonfuture tense (abbreviated NFUT) is a grammatical tense that distinguishes a verbal action as having taken place in the past or the present, as opposed to the future tense. Nonfuture tense is found in languages such as Rukai, Greenlandic, Quechua, Yabem and Nivkh.

Ancient Greek verbs have four moods (indicative, imperative, subjunctive and optative), three voices (active, middle and passive), as well as three persons (first, second and third) and three numbers (singular, dual and plural).

• In the indicative mood there are seven tenses: present, imperfect, future, aorist (the equivalent of past simple), perfect, pluperfect, and future perfect. (The last two, especially the future perfect, are rarely used).
• In the subjunctive and imperative mood, however, there are only three tenses (present, aorist, and perfect).
• The optative mood, infinitives and participles are found in four tenses (present, aorist, perfect, and future) and all three voices.

The distinction of the "tenses" in moods other than the indicative is predominantly one of aspect rather than time.

Shall and will are two of the English modal verbs. They have various uses, including the expression of propositions about the future, in what is usually referred to as the future tense of English.

Historically, prescriptive grammar stated that, when expressing pure futurity (without any additional meaning such as desire or command), shall was to be used when the subject was in the first person, and will in other cases (e.g., "On Sunday, we shall go to church, and the preacher will read the Bible.") This rule is no longer commonly adhered to by any group of English speakers, and will has essentially replaced shall in nearly all contexts.