So I've recently purchased a couple of sweater / knit dresses for fall, and they both have the same problem: in certain lights, the skirt part becomes kind of see-through, as in, it's possible to see the outline of my thighs through my dress. (Sorry, I didn't explain that well...but I assume I am not the only one to have experienced this?) I'm thinking a sort of tight slip would solve this problem, but I don't know where to find one. Any ideas or alternative solutions?

Thanks!!