Check It is the newest feature on the Read&Write for Google Chrome toolbar that will check spelling and grammar in Google Docs.
Click the Check It button to activate it while in a Google Doc and it'll check for spelling or grammar errors as well as phonetic spelling, homophones or other confusable words.
If you find an issue with Check It not finding an error or flagging text as incorrect that you feel is correct, click the More button on the right end of the Read&Write for Google Chrome toolbar
Then go to Options > Check It
From there click the link at the bottom of the screen to report any issues
For a quick overview of Check It, please watch the video below:
Hiding Check It
If you’d like to hide Check It, click the the More button on the right end of the Read&Write for Google Chrome toolbar and go to Options > Features
From there you can toggle the switch to the right of any feature to the left and that will hide that feature.
Admins can also hide Check It by contacting Technical Support by email at firstname.lastname@example.org and request that a feature be hidden for the domain