Generalize in the Plural or Use "He or She"

        Academic standards and colloquial customs now dictate that we refer to individuals without assuming we are talking about males.  This produces more wasted teachers' ink in corrections than perhaps any error other than possessive vs. contracted pronouns.  Here is an example of the problem in three papers:

A person’s car says a lot about their personality.

When purchasing a laptop the student must be aware of their own needs as well as the schools’ requirements.

        These sentences violate pronoun number agreement: singular nouns take singular pronouns / plural nouns take plural pronouns.  That rule was intended to prevent ambiguity or misunderstandings about what noun the pronoun refers to.  Consider this sentence with the pronoun pluralized to mask gender but also masking reference:

When a person takes hostages, they should be punished.

        Writers tend to use "they" and "their" to avoid the awkward-sounding but gender inclusive "he or she" and "his and hers."  Doing so usually does not create dangerous misunderstandings like the sentence above, but it will cause your instructors to mark up the paper with corrections.

        When possible, generalize in the plural, and redesign the sentence to avoid confusion about reference:

People who take hostages should be punished.