English Sentence Checking Preference Setting

I’m using LO for Mac OS. In the Preferences under Language Settings is a section called “English Sentence Checking” but it is not covered in the built-in Help nor is it covered in the Getting Started PDF for LO 4.0 (I could not find one that covers 4.2). Where can I find information on how to use this settings section?

The documentation is here:

Documentation/Publications · User Guides · Getting Started with LibreOffice · 4.2.x Branch

Chapter 2 · Setting Up LibreOffice · Choosing language settings · English sentence checking

(page 26 f.).

Thanks! I’ve bookmarked the documentation link and will download all the appropriate documentation - eventually.