Do you think I'll get married before I turn 30? - Who knows, you might never marry.
Since she hasn't studied at all I don't think she'll pass the test, but who knows? She might pull a Homer and actually pass; I doubt it though.
Who knows where he has gone.
- Onun nereye gittiğini kim bilir.
Who knows what'll happen?
- Ne olacağını kim bilir?