what is verb expressing present,past,future

Tenses determine the time of action in a sentence. There are three tenses in English grammar- present, past and future. There are four forms of a tense.

The simple form of a tense shows that an action is mentioned simple, without anything being said about the completeness or incompleteness of the action.

The continuous form of a tense shows that the action mentioned is incomplete or continuous.

The perfect form of a tense shows that the action is going on continuously, and not completed at a particular point of time.

The perfect continuous form of tense shows not only the time of an action or event but also the state of an action referred to.

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