I think you can try Ctrl+Space which is the protected space. You can even use for more than two words.
WAS On Mon, 2009-10-26 at 12:31 +0100, Matthieu Stigler wrote: > Hi > > My question seems not so complicated but I did not find on the archives.. > > I want to use the enviro description with on one line thw frist two > words (instead of the first one by default) included, as: > > \begin{description} > \item [world] it is... > \item [Earth and sun] that is... > \end{description} > > Can I do in Lyx or do I have to use it in TeX code mode? > > Thanks a lot! > > Matthieu