Once you have Wordtune installed in Chrome you can simply highlight any sentence that you have written and click the Wordtune extension to have a list of alternate wordings suggested to you. The suggested alternatives appear as a list directly below your original sentence. You can replace your original sentence with a suggested alternative by simply clicking on the suggestion that you like.
Wordtune is available in a free version and in a paid version. The free version does exactly what is outlined above and nothing else. The paid version offers additional features including a "word finder" which is basically a thesaurus and a "formality controller" which makes suggestions related to the tone of your writing.
Applications for Education
Wordtune could be a good Chrome extension for students to use to help them avoid using the same phrases and or sentence structures too often in a document.
So far I've tested Wordtune in Google Documents where it worked well. I also attempted to use it in the online version of Microsoft Word. Unfortunately, it didn't work in the online version of Word.
On a related note, here's what I look for when testing a new Chrome extension.