1. I have been there already.

2. I have already been there.
3. I was already there.
4. Already I was there.
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Are they all grammatical? Which ones are commonly used? Do we have to use the present tense or the simple past tense?

1 answer

All are grammatically correct. Only #4 is awkward. The adverb would be better placed at the end of the sentence in #4.

Either tense works fine.