When I open System Settings and open the Language Support dialog, there is an option in the list, for (I think) Chinese. As far as I can recall I have never installed this language myself.

Searching for language-pack in Synaptic, the following packages are listed as installed: language-pack-en, language-pack-en-base, language-pack-gnome-en and language-pack-gnome-en-base. If I click the Installed Languages button in the Language Support dialog, I do not see Chinese listed as installed: only English has a checkmark.

Is this additional language taking up space? How can I remove it?

Here is the output of locate language-pack:

% locate language-pack

/usr/share/doc/language-pack-en

/usr/share/doc/language-pack-en-base

/usr/share/doc/language-pack-gnome-en

/usr/share/doc/language-pack-gnome-en-base

/usr/share/doc/language-pack-en/changelog.gz

/usr/share/doc/language-pack-en/copyright

/usr/share/doc/language-pack-en-base/changelog.gz

/usr/share/doc/language-pack-en-base/copyright

/usr/share/doc/language-pack-gnome-en/changelog.gz

/usr/share/doc/language-pack-gnome-en/copyright

/usr/share/doc/language-pack-gnome-en-base/changelog.gz

/usr/share/doc/language-pack-gnome-en-base/copyright

/usr/share/locales/install-language-pack

/usr/share/locales/remove-language-pack

/var/cache/apt/archives/language-pack-en-base_1%3a11.10+20120103_all.deb

/var/cache/apt/archives/language-pack-en-base_1%3a12.04+20111229_all.deb

/var/cache/apt/archives/language-pack-en_1%3a11.10+20120103_all.deb

/var/cache/apt/archives/language-pack-en_1%3a12.04+20120202_all.deb

/var/cache/apt/archives/language-pack-gnome-en-base_1%3a11.10+20120103_all.deb

/var/cache/apt/archives/language-pack-gnome-en-base_1%3a12.04+20111229_all.deb

/var/cache/apt/archives/language-pack-gnome-en_1%3a11.10+20120103_all.deb

/var/cache/apt/archives/language-pack-gnome-en_1%3a12.04+20120202_all.deb

/var/lib/dpkg/info/language-pack-en-base.list

/var/lib/dpkg/info/language-pack-en-base.md5sums

/var/lib/dpkg/info/language-pack-en-base.postinst

/var/lib/dpkg/info/language-pack-en-base.postrm

/var/lib/dpkg/info/language-pack-en.list

/var/lib/dpkg/info/language-pack-en.md5sums

/var/lib/dpkg/info/language-pack-fr-base.list

/var/lib/dpkg/info/language-pack-fr-base.postrm

/var/lib/dpkg/info/language-pack-gnome-en-base.list

/var/lib/dpkg/info/language-pack-gnome-en-base.md5sums

/var/lib/dpkg/info/language-pack-gnome-en-base.postinst

/var/lib/dpkg/info/language-pack-gnome-en-base.postrm

/var/lib/dpkg/info/language-pack-gnome-en.list

/var/lib/dpkg/info/language-pack-gnome-en.md5sums

And here is the output of ls /usr/share/locale-langpack:

% ls /usr/share/locale-langpack 

en     en@boldquot  en_GB  en@quot  en_US

en_AU  en_CA        en_NZ  en@shaw  en_US@piglatin