Proofread Bot improves your grammar, style, and vocabulary.
The free "simple" check only looks for common style and statistical issues and can take up to 20-30 seconds to complete.
The paid "pro" grammar and style check requires a lot more resources and can take even up to 1 minute.
Proofread Bot did not catch a grammar or style error? Submit it here http://proofreadbot.com/node/add/text !
Plagiarism checks use search engines to find duplicates and require a pro package and your Bing or Google search API key. You can enter API keys at http://proofreadbot.com/user where you can also see how to obtain such keys.
You can see the list of rules at http://proofreadbot.com/rules. The number of grammar rules constantly increase, and you can suggest new ones in the support forum or at firstname.lastname@example.org.
If you like the plugin, please rate it and buy a package to support further development.