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Manuscript Preparation, Copyediting, and Proofreading
Q. Microsoft Word says that I need to put an apostrophe in the word students in the following sentence. Why? Where is the possessive? “We will be enrolling new students right up to the day school starts.”
A. Grammar-checking software is still relatively clueless. I think Word decided that right is a noun in your sentence, probably because in its unbending mind “up to the day” looks like a prepositional phrase modifying right. (Perhaps right up is a little too colloquial to compute in Word’s dictionary.) So Word thinks you are enrolling the right of new students (students’ right), up to the day school starts. Luckily, you know what you mean.