You're incorrect about the use of singular they, though: it's both correct in many contexts and widespread. See: http://www.dictionary.com/browse/they
"USAGE ALERT
Long before the use of generic 'he' was condemned as sexist, the pronouns 'they', 'their', and 'them' were used in educated speech and in all but the most formal writing to refer to singular indefinite pronouns or singular nouns of general personal reference (which are often not felt to be exclusively singular): If anyone calls, tell them I'll be back soon. A parent should read to their child.Such use is not a recent development, nor is it a mark of ignorance. Shakespeare, Swift, Shelley, Scott, and Dickens, as well as many other English and American writers, have used they and its related case forms to refer to singular antecedents. Already widespread in the language (though still rejected as ungrammatical by some), this use of they, their, and them is increasing in all but the most conservatively edited American English [...]"
You're incorrect about the use of singular they, though: it's both correct in many contexts and widespread. See: http://www.dictionary.com/browse/they
"USAGE ALERT
Long before the use of generic 'he' was condemned as sexist, the pronouns 'they', 'their', and 'them' were used in educated speech and in all but the most formal writing to refer to singular indefinite pronouns or singular nouns of general personal reference (which are often not felt to be exclusively singular): If anyone calls, tell them I'll be back soon. A parent should read to their child.Such use is not a recent development, nor is it a mark of ignorance. Shakespeare, Swift, Shelley, Scott, and Dickens, as well as many other English and American writers, have used they and its related case forms to refer to singular antecedents. Already widespread in the language (though still rejected as ungrammatical by some), this use of they, their, and them is increasing in all but the most conservatively edited American English [...]"