Tense is one of three primary temporal attributes of language (temporal meaning related to time). The other two are aktionsart, which is the temporal nature of a verb, and aspect — the temporal nature of an utterance. They are used together with perfection and mood to express time in all languages. *Remember, an utterance is the linguistic term for any formation that has a subject, verb and/or object and expresses a complete thought.
Tense represents the contrast between two measurements along the timeline of an utterance, with one of those measurements being the Time of Utterance TUTT (the time at which the actual utterance is made). TUTT is always the primary point of reference for tense. There are three additional references to which TUTT can be contrasted: TAST — the Time of Assertion, TCOM — the Time of Completion, and TEVL — the Time of Evaluation; these are secondary references. Which type is used for the secondary reference is determined by aspect and type of utterance.
TAST – Time of Assertion: This is the time at which the action of the verb takes place. It can be a single point in time (in non-durational aspects) such as in “I had dinner at 5pm.” Or, it can be a range of time (in durational aspects) such as “I was eating dinner from 5 till 7.”
TCOM – Time of Completion: This is the point in time at which a verb is completed. TCOM is used with perfected forms. In perfected non-durational aspects it represents the time by which a verb is finished, as in “I have eaten dinner.” In perfected durational aspects it represents either the time at which a verb is finished, or more normally, a time up to which the verb is completed (but that it may continue beyond); this function of allowing for interrupting of the verb is the more standard use of this form and allows the duration of the verb to be measured up to a given point (TCOM). Consider “I had been eating for 2 hours by 7pm,” in which an action (eating) has a duration, of which two hours of it is completed, as of 7pm.
TEVL – Time of Evaluation: Some utterances do not support measuring a specific action. Instead, they express a change in state, a generalization, or perhaps an habitual truth. These utterances express an idea that is evaluated as true or not. The earliest point in time at which the idea expressed (called the attestation) can be evaluated as true is the TEVL. Consider “Birds fly.” In this utterance a generalization is made (in the present) about birds and it can be immediately evaluated (present) as true. Likewise “I used to drink coffee everyday,” refers to an habitual action that was true in the past so that the TUTT is present (it is said now) but its TEVL is the past.
Present, Past, & Future
A common misconception is to mistakenly speak of the “three tenses”. Actually, aside from the true present (saying something right now that is happening right now) which can be a point (that point being right now), tenses are ranges. These ranges refer to the contrast between the primary TUTT and the secondary TAST, TCOM, or TEVL.
If the primary and secondary references occur at the same point on the timeline, an utterance is said to be in the present tense. If the primary reference occurs after the secondary reference (TAST, TCOM, or TEVL is to the left of TUTT), then that utterance is said to be in the past tense. And, if the primary reference occurs before the secondary reference (TAST, TCOM, or TEVL is to the right of TUTT), the utterance is said to be in the future tense.
The Time of Utterance is almost always the present. The only instances in which TUTT occurs in the past or future is when dealing with reported speech, i.e. “John said “He is the murderer,” (TUTT in the past)” or “John will say “He didn’t do it.” (TUTT in the future)”. Note in even these examples that the primary TUTT of the whole utterance is present, but the TUTT of the quoted utterance is in the past or future as reported.
It is best to refer to present tenses, past tenses, and future tenses rather than just tense because utterances can occur in the immediate present, general present, near future, distant past, etc with the differences in these subcategories within a range of tenses being the relative distance along the timeline between the two temporal references — the greater the distance between TUTT and TAST, TCOM, or TEVL, the farther in the past or future the tense.
Tense does not Equal Time
The word tense is often mistakenly used to refer to time in general or for anything related to time within language. Tense is not time. It is merely a contrast between temporal references as explained above. A verb cannot have tense. Verbs alone are just words. Tense is an attribute of an utterance, and a verb outside of an utterance cannot express tense because there is nothing to compare it to.
This is not to say that verbs don’t have temporal qualities. They certainly do. In fact, all verbs have a temporal nature. This temporal nature of verbs is called Aktionsart. Aktionsart in some verbs are very strong so that they generally occur in one aspect more than another such as statives or actions. Utterances also have a temporal nature, and like aktionsart does for the verb itself, aspect determines the temporal nature of the utterance itself. In English, aspect determines whether the utterance expressed duration through its structure or not. Verbs can also be completed, this is called perfecting. Verbs can be naturally perfected via their aktionsart (such as verbs that naturally occur in an instance such as die, or sneeze). Utterances can also be completed through perfecting their aspects (have eaten, have been eating).
With all this talk of aspects and aktionsarten (the plural of aktionsart (it’s German)) and perfecting, it is important to remember that while these all deal with time, they are not tenses. So, there is no such thing as the “present perfect tense” or “present progressive tense” or the “past continuous tense” or the “subjunctive tense” or “the perfect”. An utterance can occur in the perfected durational aspect in the past (I had been eating) but ‘in the past’ is the only part of that description that deals with tense.