在问题中显示的文档设置中希腊文 PDF 书签，有趣的部分是：
\documentclass[greek,english]{scrbook}
\usepackage[LGRx,T1]{fontenc} % define LGR and T1 encodings
\usepackage[utf8]{inputenc} % standard UTF-8 input encoding
\usepackage[greek,english]{babel}
\usepackage[unicode]{hyperref}
这米尼托克该包用于按章节呈现迷你目录。
\usepackage[k-loose]{minitoc} % Mini-ToCs with loose line spacing
\mtcsettitle{minitoc}{} % for empty title
\mtcsetrules{minitoc}{off} % turn off rules before and after the minitoc's
\mtcsetpagenumbers{minitoc}{off} % turn off page numbering in minitoc's
除一个部分外，其余部分标题均为希腊文。唯一的英文部分名为拇指食指并且正确（？）用英语定义\selectlanguage{english}，在 mini-ToC 中以希腊字母显示为Τηυμβ-ινδεξ。
笔记该章节标题正确显示在（正常）目录中！
应该如何米尼托克指示尊重语言设置？
答案1
示例文档中有很多方面需要纠正：
\documentclass[10pt,english,greek,BCOR=20mm, footnoterule,
lists=totoc, index=totoc, captions=bottombeside, open=any,
iso-8859-7,latin9,utf8]{scrbook}
\usepackage[LGRx,T1,LGR]{fontenc} % define LGR and T1 encodings
\usepackage[utf8]{inputenc} % standard UTF-8 input encoding
\usepackage[english,greek]{babel}
\usepackage[a4paper]{geometry}
\geometry{tmargin=20mm,bmargin=30mm,lmargin=30mm,rmargin=30mm}
\usepackage{color}
\usepackage{units}
\usepackage[normalem]{ulem}
\usepackage[k-loose]{minitoc} % loose line spaced minitoc
\mtcsettitle{minitoc}{} % for empty title
\mtcsetrules{minitoc}{off} % turn off rules before and after the minitoc's
\mtcsetpagenumbers{minitoc}{off} % turn off page numbering in minitoc's
\usepackage[unicode=true,bookmarks=true,bookmarksnumbered=true,
bookmarksopen=true,bookmarksopenlevel=1,breaklinks=true,
pdfborder={0 0 0},backref=page,colorlinks=true]{hyperref}
\usepackage{bookmark} % pdf bookmarks
\hypersetup{pdftitle={Αναφορά...},
pdfauthor={Νίκος Αλεξανδρής},
pdfsubject={Υλοποίηση...},
pdfkeywords={minitoc, greek, english, babel, unicode, LaTeX},
linkcolor=blue, anchorcolor=red, pdfstartview={FitH},
hyperfootnotes=false, unicode=true}
\usepackage{kerkis} % fonts
\usepackage[final,expansion=true,protrusion=true]{microtype} % kerning/margin
\newcommand{\code}[1]{\texttt{#1}} % Textclass specific LaTeX commands
\definecolor{lightgray}{gray}{0.2} % define lightgray
%%% Important!
\addto\extrasenglish{\def\encodingdefault{T1}\fontencoding{T1}\selectfont}
\begin{document}
\dominitoc
\title{\foreignlanguage{english}{An english minitoc-entry in an LGRX encoded document}}
\subtitle{\foreignlanguage{english}{A (not exactly Minimal) Working Example!}}
\author{του Νίκου Αλεξανδρή%
\thanks{\foreignlanguage{english}{\protect\href{mailto:nik@}{nik@}}}}
\maketitle
\tableofcontents
\chapter{Σχεδιασμός~και υλοποίηση}
\minitoc
\section{Δομή εγγράφου\label{sec:a}}
\section{Δομή σελίδας\label{sec:b}}
\begin{otherlanguage*}{english}
\begin{itemize}
\item \foreignlanguage{greek}{(ύψος κειμένου)}
$textheight:\,\unit[438]{pt}*\unit[0.3515]{mm}=\unit[153.957]{mm}$
\item \foreignlanguage{greek}{(πλάτος κειμένου)}
$textwidth:\,\unit[746]{pt}*\unit[0.3515]{mm}=\unit[262.219]{mm}$
\item
$\nicefrac{textwidth}{2}:\,\nicefrac{\unit[746]{pt}*\unit[0.3515]{mm}}{2}=\unit[131.1095]{mm}$
\end{itemize}
\end{otherlanguage*}
\subsection{Κεφαλίδες~και Υποσέλιδες~σημειώςεις}
\begin{otherlanguage*}{english}
\begin{itemize}
\item \sout{use }\emph{\sout{scrpage2}}\sout{ instead of }\emph{\sout{fancyheader}} (see also:
\href{http://tex.stackexchange.com/questions/11220/replacing-fancyhdr-with-scrpage2}%
{tex.stackexchange.com/questions/11220/replacing-fancyhdr-with-scrpage2})
\end{itemize}
\end{otherlanguage*}
\subsection{Δομή πλάγιων σελίδων}
(=\foreignlanguage{english}{landscape})
\begin{otherlanguage*}{english}
\begin{itemize}
\item balance up with respect to page width!
\item in each landscape page: 2x 48\% column width(ed) boxes
\item inside column-boxes: vertically stacked, and centered, 2x photos sized
49\% of text height
\end{itemize}
\end{otherlanguage*}
\section{\texorpdfstring{\foreignlanguage{english}{Thumb index}}{Thumb
index}}
\label{Section: Thumb - Index}
\begin{otherlanguage*}{english}
\begin{itemize}
\item using \code{chapterthumbs.sty}
by Markus Kohm (e.g., among other places also to be found at
\href{file:http://www.tex.ac.uk/tex-archive/info/examples/KOMA-Script-3/Anhang-B/source/chapterthumb.sty}%
{http://www.tex.ac.uk/tex-archive/info/examples/KOMA-Script-3/Anhang-B/source/chapterthumb.sty})
\end{itemize}
\end{otherlanguage*}
\end{document}
很少需要明确使用\selectlanguage。你给出的定义\textgreek是无用的，因为希腊语是默认语言。相反，对于英语文本，也需要类似的技巧。
直接输入σ和ς显然是可能的。
答案2
你是如何定义英语部分的？
下列
\section{\texorpdfstring{\selectlanguage{english}Thumb index}{Thumb index}}
似乎在这里工作。
答案3
遵循 Stephan Lehmke 的建议后得到一个（虽然成功但并不完全是最小的）工作示例：
\documentclass[10pt,english,greek,BCOR=20mm, footnoterule, lists=totoc, index=totoc, captions=bottombeside, open=any, iso-8859-7,latin9,utf8,english,greem]{scrbook}
\usepackage[LGRx,T1]{fontenc} % define LGR and T1 encodings
\usepackage[utf8]{inputenc} % standard UTF-8 input encoding
\usepackage[english,greek]{babel}
\usepackage[a4paper]{geometry}
\geometry{verbose,tmargin=20mm,bmargin=30mm,lmargin=30mm,rmargin=30mm}
\setlength{\parskip}{\medskipamount}
\setlength{\parindent}{0pt}
\usepackage{units}
\PassOptionsToPackage{normalem}{ulem}
\usepackage{ulem}
\usepackage[unicode=true,
bookmarks=true,bookmarksnumbered=true,bookmarksopen=true,bookmarksopenlevel=1,
breaklinks=true,pdfborder={0 0 0},backref=page,colorlinks=true]
{hyperref}
\hypersetup{pdftitle={Αναφορά...},
pdfauthor={Νίκος Αλεξανδρής},
pdfsubject={Υλοποίηση...},
pdfkeywords={minitoc, greek, english, babel, unicode, LaTeX},
linkcolor=blue, anchorcolor=red, pdfstartview={FitH}, hyperfootnotes=false, unicode=true}
\makeatletter
\DeclareRobustCommand{\greektext}{%
\fontencoding{LGR}\selectfont\def\encodingdefault{LGR}}
\DeclareRobustCommand{\textgreek}[1]{\leavevmode{\greektext #1}}
\DeclareFontEncoding{LGR}{}{}
\DeclareTextSymbol{\~}{LGR}{126}
\newcommand{\code}[1]{\texttt{#1}} % Textclass specific LaTeX commands
\usepackage{bookmark} % pdf bookmarks
\usepackage{breakurl} % breakurl's
\usepackage{kerkis} % fonts
\usepackage[final,expansion=true,protrusion=true]{microtype} % kerning/margin
\usepackage{color}
\definecolor{lightgray}{gray}{0.2} % define lightgray
\usepackage[k-loose]{minitoc} % loose line spaced minitoc
\mtcsettitle{minitoc}{} % for empty title
\mtcsetrules{minitoc}{off} % turn off rules before and after the minitoc's
\mtcsetpagenumbers{minitoc}{off} % turn off page numbering in minitoc's
\begin{document}
\title{\selectlanguage{english}An english minitoc-entry in an LGRX encoded document}
\subtitle{\selectlanguage{english}A (not exactly Minimal) Working Example!}
\author{του Νίκου Αλεξανδρή%
\thanks{\selectlanguage{english}%
\protect\href{mailto:nik@}{nik@}\selectlanguage{greek}
%
}}
\maketitle
\selectlanguage{english}%
\dominitoc
\mtcprepare
\tableofcontents{}
\selectlanguage{greek}%
\chapter{Σχεδια\textsigmaμό\textvarsigma~και υλοποίη\textsigmaη}
\minitoc
\section{Δομή εγγράφου\label{sec:=000394=0003BF=0003BC=0003AE-=0003B5=0003B3=0003B3=0003C1=0003AC=0003C6=0003BF=0003C5}}
\section{Δομή \textsigmaελίδα\textvarsigma\label{sec:=000394=0003BF=0003BC=0003AE-=0003C3=0003B5=0003BB=0003AF=0003B4=0003B1=0003C2}}
\begin{itemize}
\item (ύψο\textgreek{c} κειμένου) \foreignlanguage{english}{$textheight:\,\unit[438]{pt}*\unit[0.3515]{mm}=\unit[153.957]{mm}$}
\item (πλάτο\textgreek{c} κειμένου) \foreignlanguage{english}{$textwidth:\,\unit[746]{pt}*\unit[0.3515]{mm}=\unit[262.219]{mm}$}
\selectlanguage{english}%
\item $\nicefrac{textwidth}{2}:\,\nicefrac{\unit[746]{pt}*\unit[0.3515]{mm}}{2}=\unit[131.1095]{mm}$
\end{itemize}
\subsection{Κεφαλίδε\textvarsigma~και Υπο\textsigmaέλιδε\textvarsigma~\textsigmaημειώ\textgreek{svει}\textvarsigma}
\selectlanguage{english}%
\begin{itemize}
\item \sout{use }\emph{\sout{scrpage2}}\sout{ instead of }\emph{\sout{fancyheader}}
\foreignlanguage{greek}{(}see also:\foreignlanguage{greek}{ }\href{http://tex.stackexchange.com/questions/11220/replacing-fancyhdr-with-scrpage2}{tex.stackexchange.com/questions/11220/replacing-fancyhdr-with-scrpage2}\foreignlanguage{greek}{)}
\end{itemize}
\selectlanguage{greek}%
\subsection{Δομή πλάγιων \textsigmaελίδων}
(=\foreignlanguage{english}{landscape})
\selectlanguage{english}%
\begin{itemize}
\item balance up with respect to page width!
\item in each landscape page: 2x 48\% column width(ed) boxes
\item inside column-boxes: vertically stacked, and centered, 2x photos sized
49\% of text height
\end{itemize}
\selectlanguage{greek}%
\section{\texorpdfstring{\selectlanguage{english}Thumb index}{Thumb index}}\foreignlanguage{english}{\label{Section: Thumb - Index}}
\selectlanguage{english}%
\begin{itemize}
\item using \code{chapterthumbs.sty}
by Markus Kohm (e.g., among other places also to be found at \href{file:http://www.tex.ac.uk/tex-archive/info/examples/KOMA-Script-3/Anhang-B/source/chapterthumb.sty}{http://www.tex.ac.uk/tex-archive/info/examples/KOMA-Script-3/Anhang-B/source/chapterthumb.sty})
\end{itemize}
\end{document}