Tense indicates the time at which an action takes place. We usually speak of tense as representing past, present, or future, but in English each of these tenses also has perfect and progressive forms.
- Present: I eat an apple every day.
- Present Progressive: She is eating her lunch right now.
- Past: He ate dinner already.
- Past Perfect: They had eaten something that made them sick.
Most English tenses are formed using helping verbs or auxiliary verbs, usually forms of the verbs be, do, or have. Changes in tense can also involve changes to the base form of the verb. With the exception of the verb be, the base form of all English verbs is the same as the first person singular present tense form.