Present Perfect Tense – English editing.

A verb tense formed by combining the present tense of the verb have with the past participle of the main verb:
Subject Present Tense of ‘Have’ Past Participle of Main Verb
She has worked
They have written
Uses:
To describe an incomplete action or series of actions continuing into the present:
Engel is German by birth but has lived in Britain for the last twenty years.
To describe a past action with results continuing to the present:
Fire has damaged a disused hotel at Abingdon.
In an adverbial clause of time referring to the future:
Massive stars will collapse in on themselves when they have exhausted their nuclear fuel.
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