How does one add keyboard languages and switch between them in Linux Mint 16?

This assumes you have other languages already added in Language Support. (To check this, Menu > Language Support)

Now to make the keyboard language appear in the Panel:

• Menu > Keyboard > Layouts > Add (+)

The icon 'en' or your language should now appear in the right panel tray. Click it to switch language.

In previous Mint versions, the shortcut for switching language was LEFT SHIFT + CAPS.

It seems now there is no default, and it must be added:

• System settings > Keyboard > Layouts > Options > Switching to another layout

Keyboard Preferences is also accessible by right-clicking the language icon in the Panel.