我想這個問題已經被問過。但我就是無法解決。我有一個模板，需要用德語寫。我不明白“元音變音”。
下面是我使用的套件：
\usepackage[english,ngerman]{babel}
\usepackage[T1]{fontenc}
\usepackage[latin9]{inputenc} % tried latin1 and ansinew and utf8 too
沒有改變！
我正在研究 MiKTeX2.9 的 TexWork 。
更新 使用以下內容：
\usepackage[english,ngerman]{babel} % deutsche Trennmuster
\usepackage[T1]{fontenc} % EC-Schriften, Trennstellen nach Umlauten
\usepackage[utf8]{inputenc}
導致以下情況：
......................
TextBlockOrigin set to 0pt x 0pt
) ("C:\Program Files\MiKTeX 2.9\tex\latex\pdfpages\pdfpages.sty"
("C:\Program Files\MiKTeX 2.9\tex\latex\base\ifthen.sty")
("C:\Program Files\MiKTeX 2.9\tex\latex\tools\calc.sty")
("C:\Program Files\MiKTeX 2.9\tex\latex\eso-pic\eso-pic.sty"
("C:\Program Files\MiKTeX 2.9\tex\generic\oberdiek\atbegshi.sty"
("C:\Program Files\MiKTeX 2.9\tex\generic\oberdiek\ifpdf.sty"))
("C:\Program Files\MiKTeX 2.9\tex\latex\xcolor\xcolor.sty"
("C:\Program Files\MiKTeX 2.9\tex\latex\graphics-cfg\color.cfg")))
("C:\Program Files\MiKTeX 2.9\tex\latex\pdfpages\pppdftex.def"))
("C:\Program Files\MiKTeX 2.9\tex\latex\natbib\natbib.sty")
("C:\Program Files\MiKTeX 2.9\tex\latex\germbib\bibgerm.sty"
** Macros for german `BibTeX'ing added to Style Option `german' 20 Apr 1993 **
** idea and languages `german' and `USenglish' implemented by M. Wallmeier **
** Modified for LaTeX 2e and german.sty 2.5b by A. Scherer 1 Nov 1995 **
** Modified for ngerman.sty and babel.sty by H. Harders 21 August 2000 **)
("C:\Program Files\MiKTeX 2.9\tex\latex\tools\tabularx.sty")
("C:\Program Files\MiKTeX 2.9\tex\latex\base\makeidx.sty")
Writing index file thesis3.idx
("C:\Program Files\MiKTeX 2.9\tex\latex\nomencl\nomencl.sty")
Writing nomenclature file thesis3.nlo
! Undefined control sequence.
\GenericError ...
#4 \errhelp \@err@ ...
l.77 \pdfcompresslevel
=9
謝謝你的幫忙 ！