In grammar, a pronoun reference error occurs when a pronoun especially the pronouns "that", "those", "it" does not relate correctly to the noun it is replaces which lead to confusing, absurd or ambiguous constructions. This is called a pronoun reference error because the relationship between the pronoun and the noun it refers to that act as a reference or antecedent is not clear. This occurs in the sentence "The papers are on the desk that I corrected", in which the pronoun "that" seemed to refer to the desk when it actually refers to the paper and therefore the relationship between the pronoun "that" and the antecedent "the papers" is not clear. Thus, the type of pronoun error in this sentence is a reference or pronoun reference error.
Marginal product is the additional output produces when one more unit of labour is employed. In our case, when Elmo hires a second worker, his marginal product is 7.
