20. Which sentence is in the past perfect tense?
They will arrive tomorrow.
He had already left when I arrived.
She has watched that movie before.
I am going to the beach next weekend.



Answer :

Final answer:

The sentence in the past perfect tense is 'He had already left when I arrived.' It exemplifies the use of past perfect tense to show the sequence of events in the past.


Explanation:

The sentence in the past perfect tense is: He had already left when I arrived.

The past perfect tense is used to describe an action that happened before another action in the past. In this sentence, the action of 'leaving' (had left) occurred before the action of 'arriving' (I arrived).


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