Last week I had to check once more on the distinction between "discrete" and "discreet." And until very recently I always had to double-check myself on "antecedent" (-ent or -ant?)--then I finally realized that it comes from the present participle of "antecedere," which is a third-conjugation verb--so of course it has to be -ent! (The logic of Latin makes its spelling so much easier to remember than English spelling!) I also have to keep reminding myself that "embarrass" has two r's but "harass" has only one; I don't know why this is such a problem for me....