Editing Linguistics (section)

== Tense, Aspect, and Mood (TAM) ==

=== Tense ===
Conveys when an action happens from the speaker's perspective, relating the <u>position in time</u> of the action; a specific point in the past or future, or, in some languages, even extending to the speaker's perspective on the flow of time itself.

* '''Past''': Indicates actions or states that occurred before the moment of speaking. It can be further subdivided into categories like simple past, past continuous, past perfect, and past perfect continuous, among others, depending on how specific languages conceptualize the flow of time and action.
* '''Present''': Describes actions or states occurring at the moment of speaking, or general truths that are timeless. It can also encompass habitual actions or states that are not necessarily happening at the moment but occur regularly.
* '''Future''': Refers to actions or states that are expected to occur after the moment of speaking; future tense can have subdivisions that provide additional nuances regarding the future action's certainty, immediacy, or manner of occurrence.

Some languages extend tense beyond these basics to express a wide range of temporal nuances:

* '''Remote versus Recent/Near''': differentiate between actions that happened a long time ago versus those that occurred more recently; or those that will occur in the remote future versus those that will occur in the near future. 
* '''Imperfect versus Perfect''': imperfect tense refers to actions that were ongoing or not completed in the past, while the perfect tense indicates actions that were completed in the past and have relevance to the present.
* '''Aorist''': in some languages, the aorist tense describes actions without specifying whether they are completed or ongoing, focusing instead on the fact that an action simply occurs.

=== '''Aspect''' ===
Focuses on the internal structure of an action (how it <u>unfolds over time</u>) rather than its <u>position in time</u>; it allows speakers to provide insights into the process, completion, repetition, or duration of a described action. 

* '''Perfective''' aspect indicates that an action is viewed as a complete whole, without focusing on its internal structure. Perfective aspect often implies that the action has been completed, especially when referring to past actions, and is used to express a single, bounded event.
* '''Imperfective''' aspect focuses on the internal structure of an action, viewing it as ongoing, habitual, or incomplete. The imperfective can describe actions that were happening in the past, are happening in the present, or will be happening in the future, without specifying an endpoint.
** '''Progressive''' aspect is a subtype of the imperfective; it specifically indicates actions that are <u>ongoing at the reference time</u>. It zooms in on the process of the action.
** '''Habitual''' aspect is another subtype of the imperfective; it describes actions that occur <u>regularly or habitually over a period of time</u>.
* '''Perfect''' aspect focuses on the <u>outcome or result</u> of an action rather than the action itself. It implies that the action, which occurred in the past, has relevance or consequences for the present or future.

* '''Prospective''' aspect indicates that an action is about to happen, focusing on the period immediately before the action starts.
* '''Iterative or Frequentative''' aspect describes actions that are repeated multiple times.
* '''Stative''' aspect refers to states or conditions rather than actions, emphasizing the static nature of the verb's meaning.

Some languages (especially in the <u>Slavic</u> subfamily) have pairs of verbs that differ only in aspect, known as '''aspectual pairs'''. They consist of one verb with a <u>perfective aspect</u> and another with an <u>imperfective aspect</u>, each capturing different '''temporal contours''' of the same action.

The <u>Russian</u> verb "писать/нап-исать" (to write) demonstrates how aspectual pairs work:

# <u>Imperfective Aspect</u>: "писать" (pisat')
#* This form is used to indicate an ongoing action, a repeated action, or a general statement about the action without specifying its completion.
#* "Она пишет письмо" (Ona pisat' pis'mo) — "She writes a letter" or "She is writing a letter." Here, the action is not necessarily completed; it might be ongoing or habitual. This aspect captures the process or internal duration of the action, without indicating whether the action has been completed; it's about the action in progress or habitually done over time.
# <u>Perfective Aspect</u>: "написать" (napisat')
#* This form denotes the action's completion, focusing on the outcome rather than the process.
#* "Она написала письмо" (Ona napisala pis'mo) — "She has written a letter." The focus is on the fact that the letter has been completed. This aspect views the action as a finished whole, emphasizing the action's completed state and its results.

This distinction between perfective and imperfective aspects can intersect with tense to provide a nuanced temporal framework; in <u>Russian</u>, tense is primarily marked on the imperfective verb, while the perfective verb inherently carries a sense of completion.

Aspect can be expressed through various means depending on the language; many languages use '''affixes''' or '''verb conjugation''' to indicate aspect (morphology). In <u>periphrastic</u> languages, aspect can be indicated by '''auxiliary verbs''' or '''verb phrases''', while some languages known for '''suppletion''' use <u>entirely different verbs</u> to express aspectual distinctions.

'''Periphrasis''' uses a combination of auxiliary verbs alongside the main verb, rather than through inflection or single aspectual verbs; it allows more than one word to convey the temporal structure, phase, or continuity of the action or state described by the verb. 

The use of auxiliary (or '''helping''') verbs in combination with the main verb is central to periphrastic aspect expression; these auxiliaries modify the main verb to indicate aspectual nuances such as <u>ongoing action</u>, <u>completion</u>, or <u>repetition</u>. Unlike with inflectional strategies, the main verb often remains in a base or '''infinitive form''', and aspectual distinctions are made through the auxiliary verbs and their placement. 

Because this form of aspect expression relies on '''syntax''' (the arrangement of words) rather than '''morphology''' (word structure changes), it allows for considerable flexibility in how actions and states can be temporally framed within a sentence. 

* "She is singing;" the auxiliary verb "is" combined with the present participle "singing" expresses an ongoing action. 
* "She has sung;" the auxiliary "has" combined with the past participle "sung" indicates a completed action with relevance to the present. 
* "Elle va chanter;" (she is going to sing). The verb "va" (goes) combined with the infinitive "chanter" (to sing) expresses an action that is about to happen in the near future.

Languages that rely heavily on periphrastic constructions for aspect expression tend to be more '''analytic'''; synthetic languages tend to encode aspect directly onto the verb through inflection. Periphrastic constructions can offer a wide range of nuanced temporal distinctions, reflecting subtle differences in how an action is viewed in terms of its progress, completion, or frequency. Over time, periphrastic constructions can become '''grammaticalized''' into more condensed forms, showing how languages can evolve from more analytic to more synthetic expressions, or vice versa.

'''Suppletion''' occurs when a language uses entirely different roots to express grammatical variations such as tense, number, person, or, as in this case, aspect, which results in pairs or sets of words that are related in meaning but have no resemblance in form.

In the context of aspect, suppletive forms are used to differentiate between how an action or state is viewed in terms of its temporal flow - such as whether it is ongoing, completed, or habitual. Suppletion in aspect is less common than in tense or person marking but can be found in languages that have a high degree of irregularity or in verbs that are frequently used and thus subject to historical changes and irregularities.

A compelling example of using completely different roots to signify aspectual differences comes from <u>Irish</u> (<u>Gaelic</u>); Irish, like other <u>Celtic</u> languages, often exhibits suppletion in its verb system. The verb "to be" in Irish has the root "bí" for the present tense, which is used in contexts that suggest habitual or ongoing actions. "Bíonn siad ag siúl" – "They walk (habitually)" or "They are walking (as a general activity)." For the past tense, indicating completed actions, <u>Irish</u> uses a completely different root, "bhí." "Bhí siad ag siúl" – "They walked" or "They were walking (at a specific instance in the past)."

=== Mood ===
Conveys the speaker's '''attitude''' towards the action or state described by the verb, indicating '''modality''' - the manner in which the action is regarded or related to reality. Unlike tense, which places actions or states in time, and aspect, which describes the nature of the action's flow, mood deals with the speaker's perspective on the <u>certainty</u>, <u>necessity</u>, or <u>desirability</u> of the event, among other nuances.

* The '''indicative mood''' is the most common, used for stating facts or asking questions. It presents the action or state as <u>real</u>, <u>actual</u>, or <u>certain</u>. "She goes to school" (a statement of fact).
* The '''imperative mood''' is used for commands, requests, or prohibitions; it directly addresses the listener and expresses a '''directive'''. "Go to school!" (a command).
* The '''subjunctive mood''' is used to express wishes, hypothetical situations, demands, or conditions contrary to fact. It often indicates something <u>desired</u>, <u>possible</u>, or <u>imagined</u>. "If she were president, she would change the law" (a hypothetical situation).
* The '''conditional mood''' indicates actions or states that are dependent on certain conditions. It often expresses <u>hypothetical</u> outcomes and is sometimes considered a subcategory of the subjunctive. "She would go to school if she woke up early" (a condition and its potential outcome).
* The '''optative mood''' is found in some languages, expressing <u>wishes</u> or <u>hopes</u>. "May you have a long life!" (a wish).
* The '''jussive mood''' is used to express <u>commands</u>, <u>suggestions</u>, or <u>necessity</u>, often in the first or <u>third person</u>. "Let us pray" (a suggestion or command).

* The '''potential mood''' expresses <u>possibility</u> or <u>capability</u>. "She might go to school" (a possibility).

* The '''interrogative mood''' is recognized by some linguists, used for asking questions. "Does she go to school?" (a question).

Mood is closely related to modality, which more broadly refers to the speaker's attitude regarding the likelihood, necessity, or obligation of the action or state. Modality can be expressed through mood, but also through '''modal verbs''' ("can," "must," "should"), adverbs, or other linguistic means, depending on the language.

The expression and classification of mood can vary significantly across languages. Some languages have distinct morphological markers for mood, with specific verb forms for the subjunctive, conditional, or imperative moods. In other languages, mood may be indicated more subtly through context, word order, particles, or the use of modal auxiliary verbs without distinct morphological changes to the main verb. While the moods listed above are relatively common, individual languages may have additional moods or lack some of these categories altogether.