This is based on Print odd and even pages
The content
will always start on odd pages, with or without comments
. No need to use \newpage
or \clearpage
to go to next odd page.
In the same way, the comments
will go on even pages.
You have to fill page by page, alternating content
and comments
to keep them in sync.
\documentclass[12pt]{book}
% From https://tex.stackexchange.com/a/455318/161015
\newinsert\instructornoteinsert
\skip\instructornoteinsert=0pt
\AtBeginDocument{\dimen\instructornoteinsert=\vsize}
\count\instructornoteinsert=0
\showboxdepth=\maxdimen
\showboxbreadth=\maxdimen
\makeatletter
\output\expandafter{\the\output
\ifodd\value{page}\else
\setbox\@outputbox\vbox to\vsize{\unvbox\instructornoteinsert\vfil}%
\@outputpage
\fi
}
\newcommand{\comments}[1]{%
\insert\instructornoteinsert{%
\normalfont
\interlinepenalty0
\splittopskip0pt
\splitmaxdepth\dp\strutbox
\floatingpenalty0
\hsize\columnwidth
\@parboxrestore
#1%
\@finalstrut\strutbox
}%
}
\makeatother
\usepackage{kantlipsum}
\begin{document}
\textbf{Here is content 1, 2 and 3.}\bigskip
1. \kant[1]
2. \kant[2]
3. \kant[3]
\comments{\textbf{Long comment with line breaks to 1, 2 and 3.}\bigskip
11. \kant[11]
12. \kant[12]
}
\textbf{Here is more content: 4 and 5.}\bigskip
4. \kant[4]
5. \kant[5]
\comments{\textbf{More long comment with line breaks to 4 and 5.}\bigskip
13. \kant[13]
14. \kant[14]
}
\end{document}