Aspect  

Aspect is a grammatical element that has to do with how an action, state of being, or event as described by a verb relates to time. Aspect is often confused with tense. While tense is concerned with when the action, state of being, or event occurs (past, present, or future), aspect is concerned with how it occurs in time. It is through aspect that we understand whether an action takes place at a single point in time, during a continuous range of time, or repetitively.

Sometimes aspect is conveyed by a sentence’s structure, through a combination of particles, verbs, and verb phrases; other times, sentence structure may be used for more than one aspect, so we rely on the overall sentence to understand its temporal meaning.

The most common distinction made regarding aspect is between the perfective and imperfective aspects. While other languages mark the difference by using two separate verb forms, English does not.

The perfective aspect can be conveyed through a variety of verb structures. It is used when we draw attention to an action as a whole, summarizing it. The perfective aspect may occur in past, present, or future actions and events. For example:

The imperfective aspect, on the other hand, is used to draw attention to the action as having an internal structure (rather than as a whole, complete action). Like the perfective, this is the case regardless of when the event occurs.

One instance of the imperfective is when we relate an action that is considered to be in progress at the moment of speaking (or at the time of another event). This is usually conveyed through the continuous aspect. For example:

We also use the imperfective when we describe actions or events as occurring repetitively, either now or in the past:

This is known as the habitual aspect.

Traditionally, each verb tense is said to have four aspects, or temporal structures: the simple, the perfect, the continuous, and the perfect continuous. These traditional aspects of the tenses do not always coincide with theory on perfective aspect and imperfective aspect—it should be remembered that certain structures may express perfective aspect in some cases and imperfective aspect in others, depending on the intended meaning.

The present tense is used for repeated actions, and for actions occurring or having a result in the present. The different aspects of the present tense can be found in the table below:

Usually, the simple and the perfect aspects match up with the perfective aspect in grammatical theory. However, as mentioned, this is not always the case. It could be argued in this case that the simple aspect of the present tense actually corresponds with the imperfective aspect, since it is usually used to convey habitual acts, as in:

Like the present, the past tense also has four traditional aspects, which can be found in the table below:

The simple and perfect simple tenses generally correspond with the perfective aspect, while the continuous and perfect continuous correspond with the imperfective aspect. Again, these do not always match up along clear lines, and we should consider what the verb phrase conveys overall to decide whether the sentence has perfective or imperfective aspect.

Although English does not have an inflected verb form for future tense, there are several structures that we use to convey future meaning, namely will/would/be going to + verb. The different aspects of these structures are found in the table:

Again, the simple and perfect aspects generally correspond with perfective aspect in the future, while the continuous and perfect continuous structures correspond with the imperfective.