Pronoun Agreement - Number and Person

A singular pronoun should refer back to a singular noun (the antecedent). The pronoun should also agree in person (he, she, you, us, etc.) Remember that pronouns can refer back to other pronouns, so confirm that there is agreement in number and person.
Example: When a gymnast is in training they are at the gym at least four hours a day. (Incorrect)
When a gymnast is in training he or she is at the gym at least four hours a day. (Correct)
Many beginning gymnasts fear the sport is too challenging; but they find that with frequent practice you can learn most techniques easily. (Incorrect)
Many beginning gymnasts find the sport is too challenging; but they find that with frequent practice they can learn most techniques easily. (Correct)