\documentclass[a4paper,landscape]{slides}
\usepackage[latin1]{inputenc}
%\usepackage[utf8]{inputenc}
\newcommand{\nnewslide}[1]{\newpage {\huge \textbf{#1} \\}\\}
\newcommand{\newslide}[1]{\newpage {\large \textbf{#1} \\}\\}
\newcommand{\snewslide}[1]{\newpage {\large \textbf{#1} \\}\\}
\newcommand{\bequ}{\begin{quote}}
\newcommand{\enqu}{\end{quote}}

\setlength{\topmargin}{-20mm}
\setlength{\oddsidemargin}{-8mm}
\setlength{\evensidemargin}{-8mm}
\setlength{\textwidth}{250mm}
\setlength{\textheight}{170mm}
%%%