Verb Aspect

Rick Harrison

Verbs exhibit various changes in human languages; some tongues inflect their verbs to indicate tense (past, present, future); some inflect verbs to indicate the person and number of the subject and/or object; and some have special forms to indicate “moods” such as commands (imperatives), conditional or hypothetical statements, and so forth. An element of verb mechanics that seems to be neglected by many language designers is aspect.

(If you are not interested in invented languages but rather came here hoping to understand aspect in natural languages, read on! You will see that constructed languages provide some of the clearest examples of certain aspects.)

Aspect refers to the internal temporal constituency of an event, or the manner in which a verb’s action is distributed through the time-space continuum. Tense, on the other hand, points out the location of an event in the continuum of events.

Be advised that many of the verb forms which are traditionally called “tenses” in grammar books and foreign language text-books are actually aspects; the traditional terminology is misleading. The distinctions between she read that book, she used to read such books, and she was reading that book when I entered the room are aspectual distinctions rather than differences of tense.

Also be aware that there is no widespread agreement on terminology with regard to aspect. Among linguists, different people use the same terms in different ways; for example, the aspect which is properly called “perfect” is often called “perfective,” and this can lead to confusion when discussing languages that mark both a perfective-imperfective and a perfect-nonperfect opposition.

Not all languages have inflections or special words to mark aspect, but most languages have ways to express the meanings which are embedded in the aspectual categories. (Bulgarian has a very rich set of aspectual inflections, but some dialects of German have very few.) When explicit inflections or particles are not available to indicate aspect, languages will use less elegant methods, often involving idiomatic set phrases, such as “used to” which marks the past tense form of the habitual aspect in English. In many natural languages, we find verb forms that combine both aspect and tense, e.g. the Spanish imperfect Juan leía, “Juan was reading, Juan used to read,” which combines the past tense and imperfective aspect.

Perfective and imperfective

In the sentence she was singing when I entered, the verb “entered” presents its action as a single event with its beginning, middle, and end included; this is an example of the perfective aspect. The verb “was singing,” on the other hand, refers to an internal portion of her singing, without any reference to the beginning or end of her singing; this is an example of imperfective aspect. In other words, the perfective treats a situation as a single shapeless whole, similar to the concept of a “point” in geometry, while the imperfective looks at the situation from the inside out and admits the possibility that the situation has a temporal shape. “Situation” refers to anything that can be expressed by a verb: a “state” (a static situation that will remain the same unless something changes it), an “event” (a dynamic situation considered as a complete, single item) or a “process” (a series of dynamic transactions viewed in progress).

A few examples, provided by Comrie¹, might help us to clarify the perfective-imperfective distinction. “In French the difference between il régna (Past Definite) trente ans and il régnait (Imperfect) trente ans ‘he reigned for thirty years’ is not one of objective or subjective difference in the period of the reign; rather the former gathers the whole period of thirty years into a single complete whole, corresponding roughly to the English ‘he had a reign of thirty years,’ i.e. one single reign, while the second says rather that at any point during those thirty years he was indeed reigning... Similarly in Ancient Greek, we find the Aorist (perfective past) in ebasíleuse déka éte ‘he reigned ten years,’ or rather ‘he had a reign of ten years,’ to bring out the difference between this form and the Imperfect (imperfective past) ebasíleue déka éte ‘he reigned for ten years,’ or more explicitly ‘he was reigning during ten years.’”