To add additional languages for your keyboard

Tap the Home Button > Apps > Settings > Language & input. Tap the Settings icon to the right of LG Keyboard, tap Input language and keyboard layout, then enable the languages you want the keyboard to be able to use.

OR

Open the Notifications Panel (when entering text), tap CHOOSE INPUT METHOD > Set up input methods > the Settings icon to the right of LG Keyboard > Input language and keyboard layout, then enable the languages you want to be able to use.