The underlined pronouns in 20 sentences need correction because they don't agree with their antecedents. Your emerging copy editors provide the correct pronoun. The worksheet can be printed or used interactively online. Check to make sure you agree with it. My American English-using teacher editor colleagues and I, along with our style guide, believe a plural pronoun should follow a compound noun (as in "the city council members and the mayor"), but this sheet implies otherwise (by marking the plural pronoun as needing correction). Just a difference between American and British grammar?