Another troublesome pair suggested by Gill – the list she and her husband generated on their trip away is still going strong but I’ll get to the end one day!
So: regretfully or regrettably? These two look quite similar, but as usual have quite different meanings.
Regretfully means in a regretful manner. Regretful? Full of regret. So you are full of regret: “She walked away regretfully, upset that she had left him sinking into the mud, but with no other choice” (sometimes I do wonder where I get my examples from. All are made up out of my head).
Regrettably means unfortunately. “The mud was regrettably sticky”.
Now … apparently regretfully gets used where regrettably should be used “Regretfully, this branch is now closed” and the dictionary says that “despite objections from traditionalists, this use is now well established” but I think we now know which one to use when, don’t we!