为什么 \bf 和 \textbf 都不起作用？

Question

我在答题纸中对某些特定文本使用了 \bf、\bfseries 和 \textbf，但我无法检测出是什么导致这些在本文档中无法正常工作。您能帮忙找到吗？

\documentclass[11pt, oneside, A4paper,final,leqno]{article}
\usepackage{amsmath}
\usepackage[utf8]{vietnam}
\usepackage{amsmath, amssymb, latexsym, amscd, amsthm}
\usepackage[usenames,dvipsnames]{color}
\usepackage{phaistos}
\newcommand\myrule{$\;$\rule{1.362cm}{.4pt}}
\newcommand{\qrule}{\gray~\rule{2.9362cm}{.4pt}}
\usepackage{enumerate}
\newcommand{\middlewave}[1]{\raisebox{.2em}{\uwave{\hspace{#1}}}}

\definecolor{usethiscolorhere}{rgb}{0.86666,0.78431,0.78431}
\usepackage{framed}
\usepackage{enumitem}


\usepackage{graphics}
\usepackage{tikz}
\newcommand*\circled[1]{\tikz[baseline=(char.base)]{
            \node[shape=circle,draw,inner sep=2pt] (char) {#1};}}
\unitlength=1mm
\def\BOX{\framebox(18.55,4.5){}}
\usepackage{multicol}
\usepackage{indentfirst}
\usepackage[modulo,left, displaymath]{lineno}
\renewcommand\linenumberfont{\normalfont\bfseries\small }
%\usepackage{eurofont}
\usepackage{eurosans}
\usepackage{enumerate}
\usepackage{amsfonts}
\usepackage{curves}
\usepackage{mfpic}
\usepackage{bbding}
\usepackage{longtable}
\usepackage{xcolor}

\usepackage{graphicx}

\usepackage[mathscr]{eucal}
\usepackage{graphics, graphpap}

\usepackage{makeidx}
\makeindex
\usepackage{multicol,color}
\usepackage{indentfirst}

\renewcommand{\thefootnote}{}
\renewcommand{\proofname}{Solution}



\newcommand{\tikzcuboid}[4]{% width, height, depth, scale
\begin{tikzpicture}[scale=#4]
\foreach \x in {0,...,#1}
{   \draw (\x ,0  ,#3 ) -- (\x ,#2 ,#3 );
    \draw (\x ,#2 ,#3 ) -- (\x ,#2 ,0  );
}
\foreach \x in {0,...,#2}
{   \draw (#1 ,\x ,#3 ) -- (#1 ,\x ,0  );
    \draw (0  ,\x ,#3 ) -- (#1 ,\x ,#3 );
}
\foreach \x in {0,...,#3}
{   \draw (#1 ,0  ,\x ) -- (#1 ,#2 ,\x );
    \draw (0  ,#2 ,\x ) -- (#1 ,#2 ,\x );
}
\end{tikzpicture}
}

\newcommand{\tikzcube}[2]{% length, scale
\tikzcuboid{#1}{#1}{#1}{#2}
}

\usepackage{pgf,tikz}
\usepackage[left=1.75cm,top=1.19012473cm,right=1.919cm,bottom=1.85391469cm,bindingoffset=0.05cm]{geometry}
\usepackage{pst-coil}

\usepackage{libertineotf}
\providecommand{\hexagon}{\biolinum\Large\scshape{H\hspace{-.061em}\raisebox{-.51ex}{E}\hspace{-.061em}XAGON}}

\newcommand*\xcircled[1]{\tikz[baseline=(char.base)]{
  \node[shape=circle,draw,inner sep=1.12pt, color=red] (char) {#1};}}

\newcommand*\ycircled[1]{\tikz[baseline=(char.base)]{
  \node[shape=circle,draw,inner sep=1.12pt, color=purple] (char) {#1};}}

\newcommand*\tcircled[1]{\tikz[baseline=(char.base)]{
  \node[shape=circle,draw,inner sep=.4812pt, color=gray] (char) {#1};}}

\newcommand*\mcircled[1]{\tikz[baseline=(char.base)]{
  \node[shape=circle,draw,inner sep=1.93812pt, color=blue] (char) {#1};}}

\newcommand*\ncircled[1]{\tikz[baseline=(char.base)]{
  \node[shape=circle,draw,inner sep=1.93812pt, color=blue] (char) {#1};}}

\newcommand*\kcircled[1]{\tikz[baseline=(char.base)]{
  \node[shape=circle,draw,inner sep=1.93812pt, color=blue] (char) {#1};}}



\newcommand*\kkcircled[1]{\tikz{\draw (2,2) ellipse (.463cm and .231cm);;}}
\newcommand*\kkci[1]{\tikz{\draw (2,2) ellipse (1.9617463cm and .4231cm);;}}


\usepackage{MnSymbol}
\usepackage{bbding}


\textheight=16.325truecm
\textwidth=13.4286325truecm
\parskip=.162cm

\usepackage[absolute,overlay]{textpos}


%\usepackage[utf8]{vietnam}
\usepackage[absolute,overlay]{textpos}
\usepackage{graphicx}


\usepackage[framemethod=TikZ]{mdframed}
\definecolor{myviolet}{rgb}{0.73,0.56,0.64}

\usepackage{lipsum}

\newmdenv[%
    rightmargin=.6725964137168512402\textwidth,
    backgroundcolor=myviolet,
    linewidth=.4pt,
   innerleftmargin=2.3pt, innerrightmargin=.3pt,innertopmargin=2.3pt, innerbottommargin=2.3pt
       fontcolor=white%
]{mybox}

\newmdenv[%
    rightmargin=.695964137168512402\textwidth,
    backgroundcolor=white,
    linewidth=.4pt,
   innerleftmargin=3.3pt, innerrightmargin=.3pt,innertopmargin=0.3pt, innerbottommargin=2.3pt
       fontcolor=white%
]{mybox2}

\definecolor{babyblue}{rgb}{0.54, 0.81, 0.94}
\definecolor{aquamarine}{rgb}{0.5, 1.0, 0.83}
\definecolor{celadon}{rgb}{0.67, 0.88, 0.69}

\definecolor{bole}{rgb}{0.47, 0.27, 0.23}

\begin{document}


\begin{center}
 \bfseries{Mathematical Young Talent Search}
\end{center}
\flushleft 
\scalebox{1.542}{\bf \textcolor{purple}{MYTS Contestant Info}} 
\vspace{2ex}

%XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
\begin{minipage}[t]{11cm}
\begin{tabular}{lp{6.5cm} p{6.5cm}}
\scalebox{.983}{  \ncircled{1} }   Họ tên/Name &  \rule{7.43cm}{.24pt} 
 &    \\[6pt]
\scalebox{.983}{  \ncircled{2} }   Ngày/tháng/năm sinh& \rule{7.43cm}{.24pt}\\ [6pt]
\scalebox{.983}{  \ncircled{3} }   Trường học/School &  \rule{7.43cm}{.24pt} 
\end{tabular}
\end{minipage}
\null\hfill %\PencilRightDown
\begin{minipage}[t]{3.7295cm}
\vspace{-11.2975em}


\end{minipage}


\vspace{1.2ex}
\ScissorHollowRight\tikz \draw[dashed](-5,0)--(7,0);


%\thispagestyle{empty}
\flushleft 
\scalebox{1.542}{\bf \textcolor {blue}{\textbf MYTS Answer Form}} 

Thí sinh viết câu trả lời vào chỗ trống thích hợp dưới đây. 
%Write your answers in the space provided below so that each answer corresponds to its question number. 
\vspace{-5ex}

\begin{center}
\renewcommand{\arraystretch}{1.35752}
\addtolength{\tabcolsep}{11.2962084pt}

\begin{tabular}{@{}*{6}{r}@{}}
\textbf{\textcolor{blue}{1}}\qrule&\textbf{\textcolor{bole}{11}}\qrule &\textbf{\textcolor{purple}{21}}\qrule& \\

\textbf{\textcolor{blue}{2}}\qrule&\textbf{\textcolor{bole}{12}}\qrule &\textbf{\textcolor{purple}{22}}\qrule&\\
\textbf{\textcolor{blue}{3}}\qrule&\textbf{\textcolor{bole}{13}}\qrule &\textbf{\textcolor{purple}{23}}\qrule&\\
\textbf{\textcolor{blue}{4}}\qrule&\textbf{\textcolor{bole}{14}}\qrule &\textbf{\textcolor{purple}{24}}\qrule&\\
\textbf{\textcolor{blue}{5}}\qrule&\textbf{\textcolor{bole}{15}}\qrule &\textbf{\textcolor{purple}{25}}\qrule&\\

\textbf{\textcolor{blue}{6}}\qrule&\textbf{\textcolor{bole}{16}}\qrule &\textbf{\textcolor{purple}{26}}\qrule& \\
\textbf{\textcolor{blue}{7}}\qrule&\textbf{\textcolor{bole}{17}}\qrule &\textbf{\textcolor{purple}{27}}\qrule&\\
\textbf{\textcolor{blue}{8}}\qrule&\textbf{\textcolor{bole}{18}}\qrule &\textbf{\textcolor{purple}{28}}\qrule&\\
\textbf{\textcolor{blue}{9}}\qrule&\textbf{\textcolor{bole}{19}}\qrule &\textbf{\textcolor{purple}{29}}\qrule&\\
\textbf{\textcolor{blue}{10}}\qrule&\textbf{\textcolor{bole}{20}}\qrule &\textbf{\textcolor{purple}{30}}\qrule&\\


\end{tabular}
\end{center}

\begin{textblock}{20.5}(6.282853965, 3.675428542541095)
\begin{tikzpicture}[scale=.573]
\draw[color=gray, thick] (6.,-1.)-- (6.,-2.);
\draw[color=gray,  thick] (8.,-1.)-- (8.,-2.);
\draw[color=gray,  thick] (10.,-1.)-- (10.,-2.);
\draw[color=gray,  thick] (12.,-1.)-- (12.,-2.);
\draw[color=gray,  thick] (14.,-1.)-- (14.,-2.);
\end{tikzpicture}
\end{textblock}


\begin{textblock}{20.5}(6.282853965, 1.20435428542541095)
\begin{tikzpicture}[scale=.573]
\draw[color=gray, thick] (6.,-1.)-- (6.,-2.);
\draw[color=gray,  thick] (8.,-1.)-- (8.,-2.);
\draw[color=gray,  thick] (10.,-1.)-- (10.,-2.);
\draw[color=gray,  thick] (12.,-1.)-- (12.,-2.);
\draw[color=gray,  thick] (14.,-1.)-- (14.,-2.);
\end{tikzpicture}
\end{textblock}

\end{document}

Answer 1

你做

\usepackage[utf8]{vietnam}

因此默认字体编码是 T5。包定义的 Libertine 字体系列libertineotf不提供 T5 编码字体。事实上，您会在日志文件中看到

LaTeX Font Warning: Font shape `T5/LinuxLibertineT-TLF/m/n' undefined
(Font)              using `T5/cmr/m/n' instead on input line 147.

LaTeX Font Warning: Font shape `T5/LinuxLibertineT-TLF/b/n' undefined
(Font)              using `T5/LinuxLibertineT-TLF/m/n' instead on input line 152.

这解释了谜团。由于 LaTeX 不知道 Linux Libertine 的 T5 编码字体，因此它会进行替换。当请求粗体时，会执行另一次替换（替换b为）。但字体形状对应于标准 CM（在 T5 编码中）。mm

消除

\usepackage{libertineotf}

Answer 2

\usepackage{times}

将其添加到您的代码中它就会起作用。该包将选择 Adob​​e Times Roman（或等效字体）作为默认字体。