# Beamer - Greek - Change Language inside \author

I am trying to use pdflatex (and not XeLaTeX) for a Greek presentation. Inside authors I want to use another language (Let's say another name in English to avoid titlepage's solution. Let's suppose it was another author that needed different encoding/language for his name even if my example is not this.)

My problem is that the "changed language" by using \foreignlanguage command is still Greek and so isn't really changed.

Here is the code and the output:

\documentclass{beamer}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[english,greek]{babel}
\title{Περι λυκειακών κυμάτων \\ (Λάθη στη διδασκαλία και προσπάθεια υπέρβασης αυτών) }
\author{Θρασύβουλος μαχαίρας\\{\foreignlanguage{english} Video Editing:}
%1st alternative
%\\{\selectlanguage{english} Video Editing:}
%second alternative
%\\\begin{otherlanguage}{english}
%Video Editing:
%\end{otherlanguage}
\\ Κωστής Λελεδάκης}
\begin{document}
\section{Εισαγωγη}
\begin{frame}
\maketitle
\end{frame}
\end{document}


I also tried the commented two ways (even \selectlanguage or \begin{otherlanguage}{english}) But then the code could not compiled due to errors:

Argument of \bbl@pop@lang has an extra }. \par l.11 \ Κωστής Λελεδάκης}

and

Use of \begin doesn't match its definition. \beamer@andstripped ... Video Editing:} \\begin { otherlanguage}{english} Vi... l.11 \ Κωστής Λελεδάκης}

respectively.

Does anyone know if this is a bug or my mistake? If it is my mistake, please give me the correct way (no titlepages please... Just inside \author command)

PS: I am going to chose the simpler solution if possible with no extra packages because I suppose my request is a basic operation that beamer has to accomplish.

• I know I could try English as a first language and change every setting after that, but this is not what I am looking for. Thanks in advance. – koleygr Sep 12 '18 at 16:30

The syntax should be \foreignlanguage{english}{Video Editing:}

Off-topic: maybe it would be better to define alternative short author and short title or at least give an alternative with \texorpdf{}{} in ordre to achieve useful pdf properties.

\documentclass{beamer}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[english,greek]{babel}
\title{Περι λυκειακών κυμάτων \\ (Λάθη στη διδασκαλία και προσπάθεια υπέρβασης αυτών) }
\author{Θρασύβουλος μαχαίρας\\\foreignlanguage{english}{Video Editing:}
%1st alternative
%\\{\selectlanguage{english} Video Editing:}
%second alternative
%\\\begin{otherlanguage}{english}
%Video Editing:
%\end{otherlanguage}
\\ Κωστής Λελεδάκης}
\begin{document}
\section{Εισαγωγη}
\begin{frame}
\maketitle
\end{frame}
\end{document}


• Thank you @semcarter... Didn't imagine that \foreignlanguage asks for a second argument... even if I should. – koleygr Sep 12 '18 at 16:40