Tense
Every language has ways of talking about time. In most languages there is a variety of expressions that can be used to show when something happened or will happen. These may include temporal adverbs (soon, later, then), PPs (in the morning, after the election), NPs (last year, that week, the next day), auxiliary verbs (will, has, did), affixes on the verb, etc. The term TENSE is used only for time reference which is marked grammatically that is, by purely grammatical elements such as affixes, auxiliaries, or particles. This distinction is reflected in standard definitions of tense such as the following:
Comrie (1985): “TENSE is grammaticalised expression of location in time.”
Bybee (1985): “TENSE refers to the grammatical expression of the time of the situation described in the proposition, relative to some other time.”
Some linguists use the term TENSE only when the time reference is indicated by verbal morphology. We will take a slightly more flexible approach, as indicated above; but where we are specifically interested in verbal morphology, we will speak of MORPHOLOGICAL TENSE. Following this usage, the familiar English paradigm look, looked, will look involves a three-way semantic distinction, but only two morphological tenses: past (looked) vs. non-past (look).
As our two definitions indicate, tense systems provide a way of “locating” an event, i.e. specifying its position, in time. Notice that when we talk about time reference, we often use the vocabulary of spatial location: on the table ∼ on Tuesday; in the house ∼ in ten minutes; at school ∼ at midnight; next door ∼ next week; plan ahead, think back, etc. This is not an accident, nor is it unique to English. In many languages, there are strong similarities between the way we think and speak about time and the way we think and speak about space.
Of course, there are important differences as well. Our experience of space is normally three-dimensional, with no one direction having a specially favored status. Time is one-dimensional and moves in only one direction. Picture yourself traveling down a one-way street with no turn-offs, and you will have a good spatial analogy for thinking about tense systems. Another possible analogy, reflected in the words used to refer to time in some languages, is to picture yourself sitting on the bank of a river facing downstream. Time flows past in one direction, like the water of the river. You can “see” what has flowed past, but not what is flowing toward you.
As noted in Bybee’s definition, tense systems always define the time of a situation with reference to some other time. Normally this reference point is the time of the speech event, in which case we speak of an ABSOLUTE TENSE system. In some languages, another time can be selected as the reference point; this is called a RELATIVE TENSE system (see below).
In terms of spatial location, the place where the speaker is (i.e. the place of the speech situation) is called here. Other positions which lie in the direction toward which the speaker is facing or moving are said to be ahead or in front, while positions which lie in the opposite direction are said to be behind or in back. In terms of time reference, the time of the speech situation is called now. All times which lie in the direction of “travel” relative to this point are called FUTURE, while those in the opposite direction are called PAST.
