\definecolumnset[example][n=2]
\definecolumnset[innerexample][n=2]

\starttext

\startcolumnset[example]
\dorecurse{15}{\input knuth\par}
\startcolumnset[innerexample]
\input knuth\par
\stopcolumnset
\dorecurse{15}{\input knuth\par}
\stopcolumnset

\stoptext

but nothing happened, can I use columns inside another column?

--
Sincerely yours,
Chen
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          Zhi-chu Chen | Shanghai Synchrotron Radiation Facility
         No. 2019 | Jialuo Rd. | Jiading | Shanghai | P.R. China
             tel: 086 21 5955 3405 | zhichu.chen.googlepages.com
                                               | www.sinap.ac.cn
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