how do you like beijing .Mr smith?oh ,i--- such a beautiful

how do you like beijing .Mr smith?oh ,i___ such a beautiful city beforeA.don't visit B.didn't visit C.haven't visited D.hadn't visitedwhy didn't you go to the cinema yesterday?because i ____ the film beforeA.had seen B.have seen C.have watched D.had watched这两道题的区别是什么,