geometry 패키지에 \newgeometry 명령이 추가되었다고 nomos 교수님이 알려주셨습니다. 이 명령을 이용하여 문서 중간에서 판면 배치를 손쉽게 바꿀 수 있습니다. memoir 클래스와도 잘 어울리는 것으로 보입니다.

% !TEX TS-program = xelatex 

% !TEX encoding = UTF-8 

\documentclass{memoir} 

\usepackage{geometry}

\def\str{

\chapter{I have a dream}

\strx\newpage\strx

}

\def\strx{

Go back to Mississippi, go back to Alabama, go back to South Carolina, go back to Georgia, go back to Louisiana, go back to the slums and ghettos of our northern towns, knowing that somehow this situation can and must be changed. Let us not wallow in the land of despair. 

I say to you today, my friends... so even though we face the problems of today and tomorrow, I still have a dream. It is a dream deeply rooted in the American dream. I have a dream that one day this country will rise up and live out the true meaning of its creed : "We hold these truths to be self-evident : that all men were created equal." I have a dream that one day, on the red hills of Georgia, the sons of former slaves and the sons of previous slaveowners will be allowed to sit down together at a table of brotherhood. I have a dream that one day even the state of Mississippi, a state sweltering with the heat of injustice, sweltering with the heat of oppression, shall be transformed into an oasis of liberty and justice. I have a dream that my three little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their mind. I have a dream today. I have a dream that one day down in Alabama, with their vicious racists, with its governor having his lips dripping with the words of interposition and nullification, one day right down in Alabama little black boys and black girls will be able to join hands with little white boys and white girls like sisters and brothers. I have a dream today".

}

\begin{document} 

\newgeometry{paper=a4paper,hmargin=20mm, vmargin=20mm, head=20mm, headsep=10mm}

\str

\newgeometry{paper=a4paper,hmargin=40mm, vmargin=40mm, head=30mm, headsep=15mm}

\str

\end{document}