bell bottoms and flared jeans for women in 2011 are all about a neo-1970s style that has a hem that is at least as wide as your foot and loose at the knee
There is also one other style elements you might consider: a high waisted cut, which is desirable for the full 1970s vibe though, if you're pairing the jeans / trousers with a more modern look, a low cut waist will work just as well.
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