In linguistics, grammatical aspect is a property of a verb that defines the nature of temporal flow in the described event or state.
In most modern Indo-European languages, including English, the concept of aspect has become conflated with the concept of tense.
It is somewhat difficult to explain the idea of aspect in English because it uses the same patterns to encode in tense both the time and the aspect of a verb together.
Time signals whether an action or event happens in the past, present, or future.
Aspect signals the duration that the event covers (and perhaps its commencement, continuation, completion, or repetition, etc.).
Time and aspect do not necessarily have to be represented together; but any clear distinction has long been lost in English, where the verb tense-form now encodes both aspect and time together.
Aspect is often indicated by verbal affixes or auxiliary verbs.
In English present and past are expressed using direct modifications of the verb, which is then modified further by one or more non-simple aspects
i.e. either
progressive/continuous,
prefect/completed  or
both
Each tense is named according to its combination of aspects and time.
