have been to/have gone to

[RavenclawVD]

Could you please check if I have the correct solution for this task: "Write the sentence, using 'have (has) been'/'have (has) gone'.
Example 0. I haven't seen Kate for ages. (She/Paris/for a year)
Answer 0. She has gone to Paris for a year.

I have already come home. (I/Poland/for a year)

P.S. My try is: 1. I have been to Poland. I was there for a year.

(Can we incorporate the period "for a year" into the sentence "I have been to Poland."?)
Thank you in advance!

[Joe]

Your answer is fine.

Yes, you could add “I was there for a year”, though I don’t recommend adding gratuitous information when it doesn’t appear to have been called for in the question.

[RavenclawVD]

Thank you very much, Joe. I appreciate your reply.
So just to confirm it, we can't add the period (for a year) to the sentence with "have been to", can we?

[Joe]

The correct answer for this task is definitely NOT:

I have already come home. I have gone to Poland for a year.

Which leaves the alternative as the "correct" answer:

I have already come home. I have been in Poland for a year.

So that is what I suspect the teacher or text-book is expecting. (Note the preposition.)

I understand your dilemma. Some people might prefer:

I have already come home. I was in Poland for a year.