我对以下代码有几个疑问：
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Medium Length Graduate Curriculum Vitae
% LaTeX Template
% Version 1.1 (9/12/12)
%
% This template has been downloaded from:
% http://www.LaTeXTemplates.com
%
% Original author:
% Rensselaer Polytechnic Institute (http://www.rpi.edu/dept/arc/training/latex/resumes/)
%
% Important note:
% This template requires the res.cls file to be in the same directory as the
% .tex file. The res.cls file provides the resume style used for structuring the
% document.
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%----------------------------------------------------------------------------------------
% PACKAGES AND OTHER DOCUMENT CONFIGURATIONS
%----------------------------------------------------------------------------------------
\documentclass[margin, 10pt]{res} % Use the res.cls style, the font size can be changed to 11pt or 12pt here
\usepackage{helvet} % Default font is the helvetica postscript font
%\usepackage{newcent} % To change the default font to the new century schoolbook postscript font uncomment this line and comment the one above
\setlength{\textwidth}{5.1in} % Text width of the document
\begin{document}
%----------------------------------------------------------------------------------------
% NAME AND ADDRESS SECTION
%----------------------------------------------------------------------------------------
\moveleft.5\hoffset\centerline{\large\bf John Smith} % Your name at the top
\moveleft\hoffset\vbox{\hrule width\resumewidth height 1pt}\smallskip % Horizontal line after name; adjust line thickness by changing the '1pt'
\moveleft.5\hoffset\centerline{123 Broadway} % Your address
\moveleft.5\hoffset\centerline{City, State 12345}
\moveleft.5\hoffset\centerline{(000) 111-1111 or (111) 111-1112}
%----------------------------------------------------------------------------------------
\begin{resume}
%----------------------------------------------------------------------------------------
% OBJECTIVE SECTIONk
%----------------------------------------------------------------------------------------
\section{OBJECTIVE}
A position in the field of computers with special interests in business applications programming, information processing, and management systems.
%----------------------------------------------------------------------------------------
% EDUCATION SECTION
%----------------------------------------------------------------------------------------
\section{EDUCATION}
{\sl Bachelor of Science,} Interdisciplinary Science \\
Rensselaer Polytechnic Institute, Troy, NY, expected December 1990 \\
Concentration: Computer Science \\
Minor: Management
%----------------------------------------------------------------------------------------
% COMPUTER SKILLS SECTION
%----------------------------------------------------------------------------------------
\section{COMPUTER \\ SKILLS}
{\sl Languages \& Software:}
COBOL, IFPS, Focus, Megacalc, Pascal, Modula2, C, APL, SNOBOL, FORTRAN, LISP, SPIRES, BASIC, VSPC Autotab, IBM 370 Assembler, Lotus 1-2-3. \\
{\sl Operating Systems:} MTS, TSO, Unix.
%----------------------------------------------------------------------------------------
% PROFESSIONAL EXPERIENCE SECTION
%----------------------------------------------------------------------------------------
\section{EXPERIENCE}
{\sl Business Applications Programmer} \hfill Fall 1990 \\
Allied-Signal Bendix Friction Materials Division, Financial Planning Department, Latham, NY
\begin{itemize} \itemsep -2pt % Reduce space between items
\item Developed four ``user friendly" forecasting systems each of which produces 18 to 139 individual reports.
\item Developed or improved almost all IFPS programs used for financial reports.
\end{itemize}
{\sl Research Programmer} \hfill Summer 1990 \\
Psychology Department, Rensselaer Polytechnic Institute
\begin{itemize}
\item Performed computer aided statistical analysis of data.
\end{itemize}
{\sl Assistant Manager} \hfill Summers 1988-89 \\
Thunder Restaurant, Canton, CT
\begin{itemize}
\item Recognized need for, developed, and wrote employee training manual. Performed various duties including cooking, employee training, ordering, and inventory control.
\end{itemize}
%----------------------------------------------------------------------------------------
% COMMUNITY SERVICE SECTION
%----------------------------------------------------------------------------------------
\section{COMMUNITY \\ SERVICE}
Organized and directed the 1988 and 1989 Grand Marshall Week \\
``Basketball Marathon.'' A 24 hour charity event to benefit the Troy Boys Club. Over 250 people participated each year.
%----------------------------------------------------------------------------------------
% EXTRA-CURRICULAR ACTIVITIES SECTION
%----------------------------------------------------------------------------------------
\section{EXTRA-CURRICULAR \\ ACTIVITIES}
Elected {\it House Manager}, Rho Phi Sorority \\
Elected {\it Sports Chairman} \\
Attended Krannet Leadership Conference \\
Headed delegation to Rho Phi Congress \\
Junior varsity basketball team \\
Participant, seven intramural athletic teams
%----------------------------------------------------------------------------------------
\end{resume}
\end{document}
\moveleft.5\hoffset这里是什么意思？为什么.5后面有\moveleft，而 后面没有参数hoffset？对于
\moveleft.5\hoffset\centerline{\large\bf John Smith}，您已经有了centerline名称，但为什么还想将其移到左侧？您想让名称显示在中间，对吗？
答案1
\hoffset默认值为0pt您可以使用它的倍数<number>\hoffset，例如，它的一半.5\hoffset。可能在res.cls他们改变了它的值，所以使用它的一小部分是有意义的。- 向左移动后的命令
\centerline是将该行的内容（长度为\linewidth）居中。
geometry使用该选项加载包showframe，您就可以看到与边距有关的情况。
\usepackage[showframe]{geometry}
您会发现一些文本超出了文本区域。