A family of Microsoft word processing software products for creating web, email, and print documents.
Like the original commenter, I find this problem and others. It is now 2015. The MS Word spelling and grammar checker still often confuses plurals with possessives, misses issues of singular / plural agreement and ends sentences with prepositions. Of course, I don't have a list of specific examples. Apparently neither did the original writer. I am working and don't have time to collect them. When searching for a way to correct these errors, one only receives results that discuss how wonderful the checkers are. They are better than nothing, but they are not correct and must be corrected manually. Many people are not grammatically fluent enough to manually correct their documents. That's their fault, but it still does not correct the problems with your tool.