Correlative Conjunctions

Correlative conjunctions are paired words that work together to join two equal grammatical elements. Think of them as coordinated pairs: unlike a single coordinating conjunction, a correlative conjunction comes in two parts that surround the items being connected. The most common pairs are both...and, either...or, neither...nor, not only...but also, whether...or, not...but, and just as...so.

Where coordinating conjunctions use one word (I like tea and coffee), correlative pairs use two: I like both tea and coffee. The first word sets the expectation, and the second completes it. This parallel structure is the defining feature of correlative conjunctions — the grammatical form after the first connector must match the form after the second. You would write She is not only intelligent but also kind (adjective after each), not She is not only intelligent but also a kind person (adjective, then noun phrase — this is unbalanced).

Subject–verb agreement follows a simple nearest-noun rule, with one exception: both...and always takes a plural verb (Both the teacher and the students were surprised). For all other pairs, the verb agrees with the noun closest to it: Either the manager or the employees are responsible, but Either the employees or the manager is responsible. The same nearest-noun rule applies to pronoun agreement: Neither Sarah nor her colleagues finished their work.

When correlative conjunctions join two independent clauses, use a comma between them: Not only did she finish early, but she also helped her team. Notice the negative inversion after not only — the auxiliary verb comes before the subject: Not only did she finish, not Not only she finished. When joining words or phrases rather than full clauses, no comma is needed: We can go either by bus or by train.

Learners often struggle with either...or versus neither...nor. The rule is straightforward: use either...or for positive alternatives (You can have either cake or ice cream) and neither...nor for negative alternatives (I have neither the time nor the energy). Do not double the negative — I don't have neither time nor energy is incorrect.