One common grammar issue occurs when using a structure consisting of two parts: the correlative conjunction.
A correlative conjunction connects two equal grammatical items. Examples of correlative conjunctions include: either…or; neither…nor; and not only…but also.
Notice that a correlative conjunction consists of two parts. Because of that, if a noun follows one part of the correlative conjunction, then a noun must follow the second part. To wit, He will order either pizza or nachos. The noun pizza follows either and the noun nachos follows or.
Two agreement problems can arise when using correlative conjunctions.
The noun following the second part of the correlative conjunction must agree with the verb that comes after it. So, if that verb is plural, the noun must be plural. For example:
Every game so far this season, either the running back or the wide receiver is the leading scorer.
In the example, wide receiver is the noun following the correlative conjunction’s second part, or. The verb is comes after that noun. Since is is singular, the noun must be singular; you wouldn’t write wide receivers. If you mean for the noun to be plural, then the verb also must be plural, as in:
Every game so far this season, either the running back or the wide receivers are the leading scorer.
Note that the noun following the correlative conjunction’s first part (running back/either) can be singular. All that matters is the noun following the correlative conjunction’s second part (wide receivers/or).
In addition, pronoun agreement can be an issue. Remember that both nouns following both parts of the correlative conjunction must agree with the pronoun that refers to them. For example:
Either fresh roses or chocolates would win Laura’s heart, because they make girls go all gushy inside, he told himself.
Fresh roses and chocolates are both antecedents to which they refers. Both Fresh roses and chocolates are plural. So, the pronoun referring to them also must be plural.
A common reason for pronoun agreement errors is that one of the antecedent nouns is singular and the other is plural (Either fresh roses or a box of chocolates). In such cases, use different nouns so they either are both singular or both plural.
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