> >> Try \renewtheorem{theorem}{... the french word ...} > > Thanks, Herbert. But, where should I insert that command? > > In the preamble. Layout->Document->Preamble
I did it, but I get the following error message: LaTeX Error: Missing \begin{document}. \renewtheorem{t heorem}{FrenchTheorem} You're in trouble here. Try typing <return> to proceed. If that doesn't work, type X <return> to quit.