\documentclass[a4paper,oneside,titlepage,12pt]{article}
\usepackage[cm-default,no-math]{fontspec}
\usepackage{xunicode}
\usepackage{xltxtra}
\usepackage{amsmath}
\usepackage{xgreek}
\setmainfont[Mapping=tex-text]{DejaVu Sans}
\parindent=0in
\begin{document}
$A \subseteq B$ \\
\\
$C \subsetneq D$
\end{document}
第一个等式位于第二个等式的正中央，呈 CD 状，中间没有符号。
我还收到以下错误消息赛莱特：
! Undefined control sequence.
l.16 $C \subsetneq
D$
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.
Underfull \hbox (badness 10000) in paragraph at lines 14--17
[]
[1
] (./basic.aux) )
如果我添加 \usepackage{amssymb} 我会收到以下错误消息
! LaTeX Error: Command `\Finv' already defined.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.231 ...ol{\Finv} {\mathord}{AMSb}{"60}
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! LaTeX Error: Command `\Game' already defined.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.232 ...ol{\Game} {\mathord}{AMSb}{"61}
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! LaTeX Error: Command `\beth' already defined.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.237 ...ol{\beth} {\mathord}{AMSb}{"69}
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! LaTeX Error: Command `\gimel' already defined.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.238 ...ol{\gimel} {\mathord}{AMSb}{"6A}
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! LaTeX Error: Command `\daleth' already defined.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.239 ...ol{\daleth} {\mathord}{AMSb}{"6B}
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
) (/usr/share/texmf-texlive/tex/xelatex/xgreek/xgreek.sty
File: xgreek.sty 2008/06/22 v2.0 Package `xgreek.sty'
Package `xgreek' version 2.0 by Apostolos Syropoulos
\@attic@num=\count98
) (./basic.aux)
\openout1 = `basic.aux'.