This post follows the initial article on tense (here). The following are examples of varying combinations of tense in different statements. Remember that tense is nothing more than a contrast between the Time of Utterance (TUTT) and either the Time of Assertion (TAST), Time of Completion (TCOM), or Time of Evaluation (TEVL).
The present tenses are those in which the two contrasting time references occur at the same time. Technically there can only be one present tense in the strictest interpretation of the word — that is, a situation in which TUTT occurs at exactly the same time as TAST/TCOM/TEVL. Most languages though tend to group situations in which the secondary time reference occurs very near the primary TUTT as present. This allows for tenses such as the general present, immediate present, recent present, and such to be expressed. In actuality these tenses are actually in the future or past (happening before [past] or after [future] the TUTT, and occurring to the left [past] and right [future] of TUTT) but the temporal distance of the secondary reference from the primary is negligible, so they are generally considered present tenses. Outlined below are diagrams showing the five possible references in which present tenses occur (all diagrams represent true present tense rather than near present tenses discussed above):
TUTT coincides with TAST
The temporal relationship of verbs used in utterances occurring in non-durational aspects, in which the verb used does not have a durational aktionsart (John paints a picture.) are represented in this diagram. Generalizations and habitual truths are not included in this group (see TUTT = TEVL below). Although common in many languages, this form is quite rare in English as most verbs either have a durational aktionsart or are used in the durational aspect (English has only one durational aspect — usually called “the progressive”). In utterances of this type, the time of utterance coincides with the time of assertion. Thus, both primary and secondary reference occurs at the same time. In the diagram at left, time of utterance is given as present, but could also be in the future or the past. The utterance remains present tense however, so long as TAST coincides with TUTT on the timeline of that utterance. For example if TUTT were in the past, so long as TAST also occurs at the same time in the past as TUTT (visually at the same spot on the timeline as TUTT), the utterance is still present tense. Likewise, if TUTT is in the future, TAST may also be in the future so long as it occurs at the same time as that future TUTT (again, visually at the same spot on the timeline of the utterance). Because verbs in these forms have no measureable duration the TAST is punctular – it’s a single point along the timeline rather than a range.
TUTT coincides with TEVL
As with TUTT = TAST described above, a common present tense usage occurs with generalizations and habitual truths. These types of utterances always occur in utterances occurring in non-durational aspects. In these types of utterances, there is no specific verb occurrence to observe (and thus no assertion). Instead, the purpose of such utterances is to merely inform. In these utterances, a generalization or an habitual truth is attested as true (or questioned for trueness in interrogative forms). The earliest point at which these attestations can be evaluated as true or not serves as the secondary temporal reference for such constructions. The diagram shows this temporal relationship in the present tense with the TUTT coinciding with the TEVL. In other words, for generalizations and habituals, if the attestation may be evaluated as true immediately at the time of utterace, or to put it simply, if the the attestation being evaluated is known to be valid when the utterance is made, then the tense of the utterance is present. Examples of this in English include such statements as “John drinks coffee (generalization)” and “John goes to school everyday (habitual).”
TUTT during TAST
This diagram reflects the temporal relationship within utterances used in non-durational aspects involving activities (John paints a picture.) or other types of utterance in which the verb employed has a naturally durational aktionsart (John works for IBM.), and any durational aspect aspect utterance regardless of whether the aktionsart of the inclusive verb(s) is durational or not (John is eating pizza.). The diagram shows that for these constructions, in the present tenses, the time of utterance occurs during the time of assertion — the duration in which the verb occurs. The smaller arrows in the diagram show that while the action may begin and end before or after the time of utterance, that TUTT falls at some point within the range of the verb’s duration.
TCOM coincides with TUTT
It should be noted in this diagram and the following, that the secondary temporal reference (TCOM) is listed prior to the primary TUTT in its description. This is because TCOM – the time of completion, represents the termination of the verb, an end point. This is the diagram for perfected non-durational forms (TUTT = TAST and TUTT = TEVL) in the present tenses, often referred to as ‘the present perfect’ or ‘present perfect simple’. These types of utterances do not provide information regarding the duration of the verb, but merely establish that the assertion or attestation of the utterance is completed as of the time of utterance. In other words, the verb is finished as of now. Because TCOM always coincides with TUTT, the time of completion is always read ‘as of now.’ For this reason, specific time phrases may not be used with perfected forms in the present tenses. Examples include “John has eaten dinner,” and “They have just arrived” (both perfected TUTT = TAST), and “John has eaten dinner at that café everyday” (perfected TUTT = TEVL).
TCOM coincides with TUTT during TAST
As with the above diagram, note that the secondary temporal reference (TCOM) for this type of utterance is listed prior to the primary TUTT in its description. This is because TCOM – the time of completion, represents the termination of the verb, an end point. This is the diagram for perfected durational forms (TUTT during TAST) in the present tenses, often referred to as ‘present perfect progressive’ or ‘present perfect continuous’. Whereas in the perfected non-durational forms above, TCOM represents an absolute terminal point of the verb, in perfected durational forms, TCOM may represent either the terminal point of the verb (that time at which it is completed or finished and beyond which it does not continue), or TCOM may represent any point within the duration of the verb, up to which that completed duration can be measured. It is possible that the TAST of the verb could continue beyond the TCOM, but this is irrelevant as the focus of such utterances is not the TAST but the TCOM and its temporal relationship with TUTT. These types of utterances are normally used to provide information regarding the duration of the verb up to a given point, be that point the terminus of that verb’s duration or a point within the duration. In the pressent tenses, the duration of the verb may be measured up to the time of utterance, which is always now. Because TCOM always coincides with TUTT, the time of completion is always read ‘as of now.’ In other words, these constructions read as the verb has a given duration up to now. Thus, specific time phrases regarding the time of completion may not be used with perfected forms in the present tenses. While a specific measure of duration may be used with such utterances [explicit duration], it is not required as some verbs which have a durational aktionsart may also be conveyed as having completed duration simply by their nature [implicit duration]. Examples include “John has been eating dinner, (perfected TUTT = TAST with implicit duration)” and “It has been raining for three days (perfected TUTT = TAST with explicit duration).