I have the following Chinese related latex (Debian) packages installed:
$ dpkg -l *chinese* | grep latex| cut -d' ' -f3
latex-cjk-chinese
latex-cjk-chinese-arphic-bkai00mp
latex-cjk-chinese-arphic-bsmi00lp
latex-cjk-chinese-arphic-gbsn00lp
latex-cjk-chinese-arphic-gkai00mp
Around the block of text where I write Chinese characters, I put the CJK block (this can just as well be around the full text:
\documentclass[a4paper,12pt]{letter}
\usepackage[british]{babel}
\usepackage[utf8]{inputenc}
\usepackage{CJK}
[..]
\begin{document}
[..]
\begin{CJK*}{GB}{gbsn}
Chinese letters can be written here
% the newpage *must* be there
<span class="red">\newpage
\end{CJK*}
[..]
\end{document}
Also see the/usr/share/doc/latex-cjk-chinese/examples directory,
as with many things, there are different ways of doing it.
