GN, you could earn the Pacific Star (for qualifying time in that region) or the Burma Star (ditto) but not both medals, even though ticking both boxes. The details of duration dates and locations are given by Wiki:-
https://en.wikipedia.org/wiki/Pacific_Star
My dad got the Pacific Star awarded (though he never received it as he died in Japan as a POW). I applied for and received it, together with the corresponding 39-45 Star and War Medal, as they had not been claimed until I became NoK.
PS pipped at the post by g3, who rightly says that a bar or rosette is worn on the first medal ribbon or ribbon alone respectively to denote the other Star