Thanks for your reply. I hadn't tried that...till you suggested it. But the result in my song is "here_" (the underscore looks like a lowered hyphen" and the line doesn't extend under the subsequent note. So, thanks for the tip, but this still doesn't work for me. I tried something else, though, and I figure now that part of the problem is due to the fact that each of my one-word-over-two-notes is followed by a rest, which is ignored by the underscoring process. That is, the line continues to wherever the next note apppears, even if that's in the next bar! So, do you think this is something worthy of a bug report?!
(If I could change the melody -- which I can't -- by replacing the rest with a note not related to the one-word combo, the process would work fine if I actually type in TWO underscores for each note of the two-note combo, including the one with the actual word.)
(Also, if I were to change the second note -- from, say, a dotted quarter, to a quarter tied to an eighth -- and typed in the appropriate number of underscores, the problem still isn't solved. All I've done is mucked up the score

)
Looks like I'm back to square one. Or, bar one, if you prefer

And yes, I've only encountered this problem in this situation.