B2ConjunctionsCreated 10 May 20269 min read

Correlative Conjunctions: Rules, Pairs and Examples

Overview

Correlative conjunctions are conjunctions that come in pairs. Each half of the pair appears at a different point in the sentence, and together they frame the two elements being connected. Unlike coordinating conjunctions, which sit between two elements, or subordinating conjunctions, which open a dependent clause, correlative conjunctions bracket the connection from both sides, creating a parallel structure that distributes emphasis equally across both elements.

The defining feature of correlative conjunctions is that each half must introduce the same grammatical type. This rule, known as parallelism or parallel structure, is not optional. Violating it produces a sentence that is grammatically incorrect, and it is one of the most persistent sources of error in learner writing at this level.

English has a small set of correlative pairs, but each one carries a distinct meaning and behaves differently in terms of verb agreement and register.

The Major Correlative Pairs

Both...And

Both...and joins two elements and includes both of them. It signals addition with equal weight and is used in positive statements only.

When both...and connects two singular nouns as the subject of a sentence, the verb is always plural because the construction treats the two nouns as a combined unit of more than one.

Example

Either...Or

Either...or presents a choice between two alternatives, signalling that one of the two options applies.

Verb agreement with either...or follows the proximity rule: the verb agrees with the subject that is closer to it, which is the subject after or.

Example

Neither...Nor

Neither...nor joins two elements and excludes both of them. Because both elements are negated by neither, no additional negative word such as not or never should appear in the same clause.

The verb agreement rule is the same as for either...or: the verb agrees with the subject closer to it, the one after nor.

Example

Not Only...But Also

Not only...but also adds emphasis by presenting a second element that goes beyond what the first alone would suggest. The also is sometimes omitted in informal writing, but in formal contexts it is retained.

When not only opens a sentence and introduces the first full clause, subject-verb inversion is required in that clause. When not only appears mid-sentence without opening the clause, inversion is not needed.

Example

Whether...Or

Whether...or introduces two alternatives in the context of uncertainty, indirect questions, or conditional indifference. It signals that the main clause applies regardless of which alternative is true and appears frequently in formal and academic writing.

Example

No Sooner...Than and Hardly...When

Both pairs signal that one event followed almost immediately after another. Both require subject-verb inversion in the clause that follows no sooner or hardly.

Example

The Parallelism Rule

Parallelism is the requirement that each half of a correlative pair introduces the same grammatical structure. If one half introduces a noun, the other must introduce a noun. If one introduces an infinitive, the other must too.

The most reliable way to check for parallelism is to isolate each half of the pair and verify that the grammatical form that follows it matches the form that follows the other half.

Common Mistake

Verb Agreement with Correlative Conjunctions

Both...and always takes a plural verb, regardless of whether the joined nouns are singular or plural.

Either...or and neither...nor follow the proximity rule: the verb agrees with the subject that immediately precedes it, which is the noun or pronoun after or or nor.

Not only...but also and whether...or follow normal subject-verb agreement based on the subject of the main clause.

Example

Common Mistakes to Avoid

Mistake 1: Breaking Parallelism

The most common error with correlative conjunctions is failing to match the grammatical form on both sides of the pair.

Common Mistake

Mistake 2: Adding a Negative Word with Neither...Nor

Neither...nor already carries a double negative meaning. Adding not, never, or no anywhere in the clause creates redundant negation.

Common Mistake

Mistake 3: Wrong Verb Agreement with Either...Or and Neither...Nor

The proximity rule is consistent: it is always the subject after or or nor that determines the verb form.

Common Mistake

Mistake 4: Omitting Inversion After Not Only at the Start of a Sentence

When not only opens a sentence and introduces the first finite clause, the subject and auxiliary verb in that clause must invert.

Common Mistake

Mistake 5: Using Both...And in Negative Sentences

Both...and is used only in positive statements. In negative contexts, neither...nor is the correct form.

Common Mistake

Mistake 6: Confusing Either...Or with Both...And

Either...or signals that one of two options applies. Both...and signals that both apply. Using one in place of the other reverses the meaning of the sentence.

Common Mistake

Practice Exercises

Exercise 1: Complete with the Correct Correlative Pair

Fill in each blank with the appropriate correlative conjunction pair from the box.

both...and / either...or / neither...nor / not only...but also / whether...or

_______ the design _______ the content of the proposal impressed the client.
The schedule allows _______ a morning session _______ an afternoon session, but not both.
_______ the budget _______ the timeline has been approved yet.
_______ did the candidate meet the requirements, _______ she exceeded them in every category.
_______ the conference is held in person _______ online, all participants will receive the materials in advance.

Exercise 2: Correct the Parallelism Error

Each sentence contains a parallelism error. Rewrite the sentence so that both halves of the correlative pair introduce the same grammatical structure.

She is both a gifted teacher and teaches with patience.
The report was neither written clearly nor did it include supporting data.
Not only did he miss the meeting, but also forgetting to send the agenda.
The manager either will call you this afternoon or sends an email by end of day.
Whether accepting the offer or to reject it, she knew the decision would affect her career.

Exercise 3: Choose the Correct Verb Form

Choose the verb form that agrees correctly with the subject in each sentence.

Neither the coordinator nor the volunteers (was / were) available on that date.
Both the report and the presentation (needs / need) to be submitted by Friday.
Either the senior analyst or the junior analysts (prepares / prepare) the weekly summary.
Neither the evidence nor the arguments (was / were) persuasive enough to change the outcome.
Both the director and the board (has / have) approved the revised proposal.

Summary

Pair	Meaning	Verb Agreement	Example
both...and	Includes both elements	Always plural	Both the plan and the budget need revision.
either...or	One of two alternatives	Agrees with nearer subject	Either the staff or the manager is available.
neither...nor	Excludes both elements	Agrees with nearer subject	Neither the draft nor the notes were attached.
not only...but also	Adds emphasis beyond the expected	Normal agreement; inversion when opening	Not only did she pass, but she also topped the class.
whether...or	Both alternatives lead to the same outcome	Normal agreement	Whether by email or by post, the form must arrive by Friday.

Correlative conjunctions impose two non-negotiable demands: parallelism between the elements they connect, and correct verb agreement based on the pair in use. Meeting both demands consistently is what separates writing that is merely grammatical from writing that is precise and well-controlled.