how do I ask this question : whose beer ?"
someone I don't know leave a glass of beer on my desk, and I want to know who leave it, then how do I ask ?

1. Whose beer ?
2. Whose beer is it ?
3. else..

Thanks for teaching.

Question

how do I ask this question : whose beer ?"
someone I don't know leave a glass of beer on my desk, and I want to know who leave it, then how do I ask ?

1. Whose beer ?
2. Whose beer is it ?
3. else..

Thanks for teaching.

Answer

Yes "Whose beer is this?" would be correct. You could also just point at it and say "Whose is this?"

Answer

Or a more open question to your bystanders: Do you know whose beer this is?