he other
<a href="definitions.html#TERMS_FILLED">fill modes</a>,
as well as with the no-fill modes.  The reason is that when text is
justified, the word spacing may expand to fill the line, but that
doesn't happen until <em>after</em> the line has been processed
in all other respects &mdash; including establishing how long to
make an underscore.  A workaround is to prepend the backslash
character <nobr>(<kbd>\</kbd>)</nobr> to each word space in the
string passed to <strong>UNDERSCORE</strong>.  The word sp