[http://source.contextgarden.net/tex/context/base/page-imp.tex page-imp.tex] defines some hany macros for handling import of existing PDF documents.
To include only a specific page from a PDF document you can write
<texcode>
<texcode>
\filterpages[file.pdf][1,3,4:6][width=18cm]
</texcode>
to insert pages 1, 3 , 4, 5 and 4 6 or
<texcode>
\filterpages[file.pdf][even][width=18cm] % even/odd
</texcode>
to insert even/odd pages up to the page 30.(See also Taco's hack in [[Processing Lists]] for handling ranges of numbers or [http://archive.contextgarden.net/thread/20050704.222033.bbadb15a.en.html this] thread in the mailing list.)
Yet another alternative is
\stoppagecomment
</texcode>
{{todo|prepare a graphics for each example}}
[[Category:PDF]]