How do I get a queen checkmate.

Does anybody know how to get a queen checkmate, you see, I don't know how to and i'm quite confused, do I just trap a king with a queen, or do I do other stuff. And how do I get a queen checkmate achievement, and lastly, does anybody know why achievement icons don't show up, they still look like they are locked even though I did what I had to do. aahgiudhsyvikjahuygdushaudbcigaudgygudgysagugdugaugdggdudiudgiuagidhaushiausgdusgaudgsaugsdugdsudgaiud ( that was to get acheive)