I've never been able to pronounce "rue" properly. It's one of those words that sounds simple but trips me up every time. I think it's because I'm used to saying "roo" instead of the actual French-influenced "roo" or "roo" with a soft "u." It's not that I don't know the word, but the pronunciation feels foreign. Maybe it's just a personal hurdle, but it's one I've never cracked.