title: Is there a rich text editor control that does both spell AND grammar checking?
body: <p>I'm looking for a winforms or wpf control that can do both spelling and grammar checking in english and also do red &amp; green squiggly underlines, similar to MS Word.</p>
  
  <p>So far, all I've been able to find are spell-checker controls.  I'd be open to good spell checking and grammar checking libraries as well - if you can recommend an integration point with the editor that allows for the underlining.</p>