这是一个简单的例子：
\documentclass{article}
\usepackage{polyglossia}
\setdefaultlanguage{german}
\begin{document}
Hallo Welt!
\end{document}
错误信息如下：
(/mnt/software/texlive/2015/texmf-dist/tex/luatex/ctablestack/ctablestack.sty)))
(/mnt/software/texlive/2015/texmf-dist/tex/latex/polyglossia/gloss-german.ldf
Package polyglossia Warning: \setlocalhyphenmin useless for unknown language ger
man on input line 6.
Package polyglossia Warning: You asked for `ngerman' but only `german' hyphenati
on is available! on input line 68.
(/mnt/software/texlive/2015/texmf-dist/tex/latex/polyglossia/babelsh.def))
(./test2.aux
! You can't use `\relax' after \the.
<recently read> \l@german
l.3 \select@language {german}
?
设置\setdefaultlanguage{english}效果良好。
谢谢乔治
german更新：如果将 替换为，上面的最小示例可以正常工作ngerman。然而，再次添加该行\usepackage{biblatex}会产生错误。这是一个最小的例子：
\documentclass{article}
\usepackage{polyglossia}\setdefaultlanguage{ngerman}
\usepackage{biblatex}
\begin{document}
Hallo Welt!
\end{document}
错误信息如下：
(/mnt/software/texlive/2015/texmf-dist/tex/latex/biblatex/biblatex.cfg)))
Package biblatex Warning: Upgrade package 'polyglossia' to >v1.42.0 recommended.
! Package biblatex Error: No default polyglossia language defined.
See the biblatex package documentation for explanation.
Type H <return> for immediate help.
...
l.6 \begin{document}
?