\input eplain

\hruledefaultheight = 4pt
\hruledefaultdepth = 8pt

\vruledefaultwidth = 36pt

\vglue 1in

\line{\leaders\ehrule\hfil gA}%

\smallskip
\ehrule
\medskip

\noindent \evrule \quad Greetings
\smallskip
\vbox to 3in{\leaders\evrule\vfil gB}

\hbox to 40pt{\downbracefill} % uses \vrule 
\bye