在 letteracdp 包中，你输入信件主题，编译文档时，TeXLive 会将主题放在Oggetto:前面。我想将其改为Subject:
答案1
该letteracdp课程是专门为意大利语量身定制的。但是，它定义了一些具有常见模式的“固定词”：
\newcommand*\subjectname {Oggetto:}
\newcommand*\registeredname {Raccomandata}
\newcommand*\registeredRRname{\registeredname~A.R.}
\newcommand*\andccname {e~p.~c.}
\newcommand*\ccname {P.~c.:}
\newcommand*\enclname {Allegati:}
\newcommand*\PSname {P.S.:}
\newcommand*\headtoname {A:}
\newcommand*\lettername {Lettera}
因此，在这种情况下，只需重新定义适当的命令即可
\renewcommand\subjectname{Subject:}
或者
\addto\captionsenglish{\renewcommand\subjectname{Subject:}}
如果您正在使用babel。
答案2
实际上有一个更好的解决方案，我计划将其包含在下一个版本的CDP 捆绑包（顺便说一句，我从 2010 年起就一直承诺会发布这样的“下一个版本”，版本 0.34 可以追溯到 2006 年；但该软件包的大部分内容都是十五年前编写的，现在需要彻底重新设计...）。
首先，将以下包添加到您的本地 TeX 树中，名称如下cdpbabel.sty：
%%------------- Identification -------------%%
\NeedsTeXFormat{LaTeX2e}[1998/09/02] % LaTeX2e is required!
\ProvidesPackage{cdpbabel}
[2014/07/20 v0.03 (**development**)]
\@ifdefinable\@cdpbabel{\def\@cdpbabel{cdpbabel}}
%%-------------- Initial Code --------------%%
\def\do#1{\@ifdefinable #1{\let #1\@empty}}
\do\@cdpbabel@perform@redefinitions
\do\@cdpbabel@letter@names
\do\@cdpbabel@artlet@names
%%--------- Declaration of Options ---------%%
\DeclareOption*{%
\IfFileExists{cdpnames\CurrentOption.ldf}{%
\input{cdpnames\CurrentOption.ldf}%
\edef\do##1{%
\noexpand\g@addto@macro
\noexpand\@cdpbabel@perform@redefinitions
{%
\noexpand\addto \csname captions\CurrentOption \endcsname
{##1}%
}%
}%
\@ifclassloaded{letteracdp}{%
\expandafter\do \expandafter{\@cdpbabel@letter@names}%
}{}%
\@ifclassloaded{articoletteracdp}{%
\expandafter\do \expandafter{\@cdpbabel@artlet@names}%
}{}%
\PackageInfo{\@cdpbabel}{%
Redefined the names of "C.D.P. Bundle" captions\MessageBreak
for the language `\CurrentOption'%
}%
}{%
\PackageError{\@cdpbabel}{%
Name def. file `cdpnames\CurrentOption.ldf' not found%
}{%
Files of the form `cdpnames<language>.ldf' are meant
to define the names\MessageBreak
in the language <language> of some captions used by
the "C.D.P. Bundle".\MessageBreak
You requested\MessageBreak
\space\space<language> = `\CurrentOption',\MessageBreak
but the corresponding file is missing; therefore,
probably some of these\MessageBreak
captions will not be printed as intended.\MessageBreak
This error affects only the \@cdpbabel\space package,
but not the babel package.\MessageBreak
You may continue:
type \space <return> \space to proceed.%
}%
}%
\PassOptionsToPackage{\CurrentOption}{babel}%
}
%%----------- Options Processing -----------%%
\ProcessOptions*
\let \do = \@undefined
\let \@cdpbabel@letter@names = \@undefined
\let \@cdpbabel@artlet@names = \@undefined
%%-------- Package and Class Loading -------%%
\RequirePackage{babel}
%%---------------- Main Code ---------------%%
\@cdpbabel@perform@redefinitions
\let \@cdpbabel@perform@redefinitions = \@undefined
%%--------------- End of Code --------------%%
\endinput
其次，添加以下语言定义文件（针对英语），名为cdpnamesenglish.ldf：
\ProvidesFile{cdpnamesenglish.ldf}[2014/07/20]
\def\@cdpbabel@letter@names{%
\def\subjectname {Subject:}%
\def\registeredname {Registered}%
\def\registeredRRname {\registeredname~R.R.}%
\def\andccname {cc}%
\def\ccname {cc:}%
\def\enclname {Encl:}%
\def\PSname {P.S.:}%
\def\headtoname {To:}%
}
\def\@cdpbabel@artlet@names{%
\def\contentsname {Contents}%
% \def\listfigurename {List of figures}%
% \def\listtablename {List of tables}%
% \def\refname {References}%
% \def\indexname {Index}%
% \def\figurename {Figure}%
% \def\tablename {Table}%
}
\endinput
其他语言以相同的方式处理；例如，对于意大利语，请添加以下cdpnamesitalian.ldf文件：
\ProvidesFile{cdpnamesitalian.ldf}[2014/07/20]
\def\@cdpbabel@letter@names{%
\def\subjectname {Oggetto:}%
\def\registeredname {Raccomandata}%
\def\registeredRRname {\registeredname~A.R.}%
\def\andccname {e~p.~c.}%
\def\ccname {P.~c.:}%
\def\enclname {Allegati:}%
\def\PSname {P.S.:}%
\def\headtoname {A:}%
}
\def\@cdpbabel@artlet@names{%
\def\contentsname {Sommario}%
\def\listfigurename {Indice delle figure}%
\def\listtablename {Indice delle tabelle}%
\def\refname {Testi citati}%
% \def\indexname {Indice analitico}%
% \def\figurename {Figura}%
% \def\tablename {Tabella}%
}
\endinput
（当然，任何人只要愿意承担这项非常简单的任务，即为另一种语言编写类似的文件，我们都非常欢迎。）
现在您可以使用新的cdpbabel包反而的babel：
\documentclass
[boldsubject,italicsignature,shortindent]
{letteracdp}
\usepackage[T1]{fontenc}
\usepackage[english]{cdpbabel}
% Note that we do **not** load "babel" directly.
\address{
Gustavo \textsc{Mezzetti}\\
L.S.U. <<A.~di~Savoia Duca d'Aosta>>\\
Via del Santo, 57\\
I--35123\quad Padova\quad Italy
}
\signature{Gustavo}
\place{Padova}
\pagestyle{headings}
\begin{document}
\begin{letter}[Whom it may concern]{
To whom it may concern
}[
The optional subject of the letter.
]
\opening{Dear Someone,}
this is the text of the letter. We start another page to show that
\verb|\headtoname| produces ``\headtoname''.
\newpage
See?
A list of enclosures is added at the end, too, just to demonstrate that
\verb|\enclname| produces ``\enclname''.
\closing{Best regards.}
\begin{enclosures}
\item The first document.
\item The second document.
\item And so on.
\end{enclosures}
\end{letter}
\end{document}
就这样！结果如下：
