\ybaselineshift10pt
\parindent5pt
\showboxbreadth10000
\showboxdepth10000
\tracingonline1
\setbox0=\vbox{\hsize=40pt%
  {\ybaselineshift0pt oお\par fiか\par
	\global\setbox4=\lastbox\unskip\unskip
   	\global\setbox5=\lastbox\unskip\unskip
  }
  \leavevmode\hbox{}いi\par uう\par えe\par
  \setbox1=\lastbox\unskip\unskip
  \setbox2=\lastbox\unskip\unskip
  \setbox3=\lastbox\unskip\unskip

  \hsize=200pt
  \leavevmode\unhcopy3\unhcopy1\unhcopy4\unhcopy5\unhcopy2

  %\showbox1\showbox2\showbox3\showbox4\showbox5
}\unvbox0

\end

