% $B%k%S(B $BH~J8=q(B
\def\ruby#1#2{%
  \leavevmode%
  \setbox0=\hbox{#1}\setbox1=\hbox{\tiny #2}%
  \ifdim\wd0>\wd1 \dimen0=\wd0 \else \dimen0=\wd1 \fi
  \hbox{\kanjiskip=\fill
  \vbox{\hbox to \dimen0{\tiny \hfil#2\hfil}%
  \nointerlineskip
  \hbox to \dimen0{\hfil#1\hfil}}}}
