I wonder if you could tell me the difference(s) between the following questions:
If you could have lived in another period, which period would you choose?
If you could live in another period, which period would you choose?
To keep it simple, the first example is in Past Tense, while the second is in Present Tense.
If you could have lived in another period, which period would you choose?
Here, one (person) asks another if he/she had gotten a chance to live in another period, the which would it have been.
If you could live in another period, which period would you choose?
Here, one (person) asks another if he/she gets a chance to live in another period, which will it be.