> Predict the output of the following *roff input. > [...]
I guessed wrong. And Heirloom nroff behaves differently from groff. Some more unexpected behavior can be seen by shortening the line length to just 1 en. I also tried the same thing in TeX and learned that by default TeX doesn't hyphenate the first word of a paragraph. (I didn't know this before, but I also never yet had to deal with a document where this was necessary.) Also interesting to see that in this word, the hyphenation patterns don't suggest a hyphenation opportunity after "anti".
