diff --git a/slides/chapter-15.de.md b/slides/chapter-15.de.md
index 9d83473..b27d2ac 100644
--- a/slides/chapter-15.de.md
+++ b/slides/chapter-15.de.md
@@ -198,14 +198,14 @@ Weitere nützliche Pakete
pdfpages |
- Einbinden von pdf-Dateien |
+ Einbinden von PDF-Dateien |
subcaption |
- Unterabbildungen und zusätzliche Möglichkeiten für Blidunterschriften |
+ Verschachtelte Abbildungen und ausgefeilte Bildunterschriften |
colortbl, tabularx, multirow, makecell |
Gestalten von Tabellen |
-
\ No newline at end of file
+
diff --git a/slides/chapter-15.en.md b/slides/chapter-15.en.md
index e69de29..52931b0 100644
--- a/slides/chapter-15.en.md
+++ b/slides/chapter-15.en.md
@@ -0,0 +1,212 @@
+@slide(layout=chapter-slide)
+
+@title
+Package in sight!
+
+@slide(layout=content-and-preview)
+
+@title
+Creating an index
+
+@content
+```{.lang-tex .hljs}
+\usepackage{makeidx}
+\makeindex
+\begin{document}
+\maketitle
+\section{What is LaTeX\index{LaTeX}?}
+LaTeX\index{LaTeX} is a typesetting
+system\index{Typesetting system}.
+\newpage \section{TeX\index{TeX} vs.
+LaTeX\index{LaTeX}} It is based on
+TeX\index{TeX}, an invention by
+Donald Knuth\index{Knuth, Donald}.
+As TeX\index{TeX} is way more complex
+syntactically than LaTeX\index{LaTeX},
+LaTeX\index{LaTeX} is much more
+popular.
+\printindex
+```
+
+@preview
+
+
+@slide(layout=content-and-preview)
+
+@title
+Designing presentation slides
+
+@content
+For slides, there is the `beamer` document class, as well as numerous [templates and themes](https://www.overleaf.com/learn/latex/Beamer).
+
+```{.lang-tex .hljs .small-text}
+\documentclass{beamer}
+\usetheme{Frankfurt}
+\usecolortheme{seahorse}
+\usepackage[utf8]{inputenc}
+
+\begin{document}
+\begin{frame}
+ \frametitle{Lemon sorbet}
+ \framesubtitle{Incarnation of good?}
+ \begin{definition}
+ A lemon sorbet is a
+ semi-frozen \textbf{dessert}
+ on \textit{lemon} base.
+ \end{definition}
+\end{frame}
+\end{document}
+```
+
+@preview
+
+
+
+@slide(layout=content-and-preview)
+
+@title
+Drawing images
+
+@content
+`TikZ` (“TikZ ist kein Zeichenprogramm” — “TikZ is no drawing software”) is a powerful package for drawing vector graphics.
+
+```{.lang-tex .hljs .small-text .scroll-one-half}
+% …
+\tikzstyle{every node}=[draw=black,thick,anchor=west]
+\tikzstyle{selected}=[draw=red,fill=red!30]
+\tikzstyle{dir}=[fill=gray!50]
+\tikzstyle{relativeTo}=[fill=blue!70]
+\begin{tikzpicture}[%
+grow via
+three points={one child at (0.5,-0.7) and
+two children at
+(0.5,-0.7) and (0.5,-1.4)},
+edge from
+parent path={(\tikzparentnode.south)
+ |- (\tikzchildnode.west)}]
+\node {/ oder C:}
+child { node {home}
+ child { node {knut}
+ child { node {pictures}}
+ child { node {docs}
+ child { node [dir] {latex}
+ child { node [relativeTo] {main.tex}
+ child { node [selected] {part1.tex}
+ }
+ }
+ }
+};
+\end{tikzpicture}
+```
+
+@preview
+
+
+
+@slide(layout=content-and-preview)
+
+@title
+Linguistics
+
+@content
+The `qtree` package can render constituent-based parse trees:
+
+```{.lang-tex .hljs}
+\Tree [.S [.NP LaTeX ]
+[.VP [.V is ] [.NP fun ] ] ]
+```
+
+@preview
+
+
+@slide(layout=content-and-preview)
+
+@title
+Mathematical proofs
+
+@content
+Logical tableaux can be renderd using the `prftree` package.
+
+```{.hljs .lang-tex .small-text .scroll-one-half}
+\begin{displaymath}
+\prftree[l,r]{}{[comp$\_{ns}$]}
+{
+ \prftree[l,r]{}{[comp$\_{ns}$]}
+ {
+ \prftree[l,r]{}{[ass$\_{ns}$]}
+ {
+ -
+ }
+ {
+ (\texttt{m:=a}, \sigma\_{\bot,\bot})
+ \rightarrow \sigma\_{48,\bot}
+ }
+ }
+ {
+ \prftree[l,r]{}{[ass$\_{ns}$]}
+ {
+ -
+ }
+ {
+ (\texttt{n:=b}, \sigma\_{48,\bot})
+ \rightarrow \sigma\_{48,18}
+ }
+ }
+ {
+ (\texttt{m:=a; n:=b}, \sigma\_{\bot,\bot})
+ \rightarrow \sigma\_{48,18}
+ }
+}
+{
+ \prftree[l,r]{}{}
+ {
+ \dots
+ }
+ {
+ \textbf{[1]}\ (\texttt{LOOP}, \sigma\_{48,18})
+ \rightarrow \sigma\_{6,6}
+ }
+}
+{
+ (\texttt{m:=a; n:=b; LOOP}, \sigma\_{\bot,\bot})
+ \rightarrow \sigma\_{6,6}
+}
+\end{displaymath}
+```
+
+@preview
+
+
+@slide(layout=content-only)
+
+@title
+Other useful packages
+
+@content
+
+
diff --git a/svg/chapter-15/beamer-crop.svg b/svg/chapter-15/beamer-crop.svg
index e2e94ae..d0483f3 100644
--- a/svg/chapter-15/beamer-crop.svg
+++ b/svg/chapter-15/beamer-crop.svg
@@ -6,32 +6,32 @@
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diff --git a/svg/chapter-15/beamer-orig.svg b/svg/chapter-15/beamer-orig.svg
index d999630..204ffd3 100644
--- a/svg/chapter-15/beamer-orig.svg
+++ b/svg/chapter-15/beamer-orig.svg
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diff --git a/svg/chapter-15/beamer.tex b/svg/chapter-15/beamer.tex
index 3445e2c..ded0e75 100644
--- a/svg/chapter-15/beamer.tex
+++ b/svg/chapter-15/beamer.tex
@@ -6,13 +6,13 @@
\begin{document}
\begin{frame}
- \frametitle{Zitronensorbet}
- \framesubtitle{Inkarnation des Guten?}
+ \frametitle{Lemon sorbet}
+ \framesubtitle{Incarnation of good?}
\begin{definition}
- Ein Zitronensorbet ist eine
- halbgefrorene \textbf{Speiseeiscreme}
- auf Basis von \textit{Zitronen}.
+ A lemon sorbet is a
+ semi-frozen \textbf{dessert}
+ on \textit{lemon} base.
\end{definition}
\end{frame}
-\end{document}
\ No newline at end of file
+\end{document}
diff --git a/svg/chapter-15/index_en-crop.svg b/svg/chapter-15/index_en-crop.svg
new file mode 100644
index 0000000..cf321f6
--- /dev/null
+++ b/svg/chapter-15/index_en-crop.svg
@@ -0,0 +1,185 @@
+
+
diff --git a/svg/chapter-15/index_en-orig.svg b/svg/chapter-15/index_en-orig.svg
new file mode 100644
index 0000000..c3739ed
--- /dev/null
+++ b/svg/chapter-15/index_en-orig.svg
@@ -0,0 +1,185 @@
+
+
diff --git a/svg/chapter-15/index_en.tex b/svg/chapter-15/index_en.tex
new file mode 100644
index 0000000..2183ddf
--- /dev/null
+++ b/svg/chapter-15/index_en.tex
@@ -0,0 +1,13 @@
+% This document is fake.
+% It is supposed to look like the german image, but it is not really an index.
+\documentclass[a4paper, 12pt]{article}
+\usepackage[utf8]{inputenc}
+\usepackage[T1]{fontenc}
+\begin{document}
+\thispagestyle{empty}
+\section*{Index}
+Knuth, Donald, 2 \\\bigskip
+LaTeX, 1, 2 \\\bigskip
+TeX, 2 \\
+Typesetting system, 1
+\end{document}