De acordo com o suporte ao Google Chromebook :
You can adjust the language used for your screens and menus, spell-check, and for viewing webpages. If you haven’t already, sign in to your Chromebook. Click the status area in the lower-right corner, where your account picture appears. Select Settings. Click Show advanced settings at the bottom of the page. In the “Language” section, click Customize languages and input. You can then adjust the following settings: