Consonant Sound /f/
Word lists for the various spellings of the /f/ sound have been added to the Page Consonant Sounds by Spelling.
It contains one list that treats ugh as a spelling of /f/ in six words (and their derivatives,) those being laugh, cough, rough, tough, trough and enough. This is a relatively trivial matter, but the reasons for doing so are discussed at the bottom of that particular word list. As explained there, the alternative is to treat the digraph gh as representing two sounds, the /g/ in ghost and the /f/ in rough. There are disadvantages in doing so, as detailed in the explanation.
Once I get the consonant word lists completed, I’m intending to refocus on the vision side of things as I believe that vision problems and “dyslexia” as we understand it are inextricably linked and this is the far more important area to investigate. In fact, dyslexia wasn’t so common, I suspect all of the focus on word lists would disappear. People would just learn to read. Word lists are just one more work-around that we utilize in our quest to help kids learn how English is structured. But we are more or less forced to take these steps because the dyslexics infer so little information about print on their own. Essentially, we’re getting the cart before the horse in much of what we do in reading instruction, I think.
But enough on that. Here again is the link to the Page Consonant Sounds by Spelling. The four lists of /f/ spellings are currently at the bottom of that Page.