I have this:

```
\documentclass[a4paper,12pt]{article}
\usepackage[utf8]{inputenc}
\usepackage[greek,english]{babel}
\usepackage{lmodern}
\begin{document}
Hello \textgreek{κόσμος}.
\end{document}

```

However, it gives me this error:

```
! Package babel Error: Unknown option `greek'. Either you misspelled it
(babel)                or the language definition file greek.ldf was not found.

```

So I [looked](https://tex.stackexchange.com/questions/139700/package-babel-error-unknown-option-francais) [around](https://tex.stackexchange.com/questions/5085/how-to-install-a-latex-package-in-macos-texlive) and it says to try installing the texlive package. However, all the instructions are for Linux. So I tried it on Mac, but package not found:

```
$ sudo tlmgr install texlive-lang-greek
tlmgr: package repository http://ctan.math.illinois.edu/systems/texlive/tlnet (verified)
tlmgr install: package texlive-lang-greek not present in repository.
tlmgr: action install returned an error; continuing.
tlmgr: An error has occurred. See above messages. Exiting.

```

How do I get this working?