Linking language · Correlative pairs

Correlative pairs connectors in English

These connectors tell the reader that two elements are joined as a pair, and the sentence needs both halves. Use a correlative pair when two things must be presented together: two options, two things both being ruled out, or two things both being true. They make a sentence feel deliberate — but only if both halves are built the same way.

5 connectorseach with where it goes and how it is punctuated

2 worked examplesthe relationship, explained

2 common mistakeswith the repair

4 exercisesrelationship first, then the word

Start here · the long version

What correlative pairs connectors really claim

Correlative connectors come in pairs that split across a sentence, and neither half works without the other.

Two halves, one structure

“Not only … but also”, “both … and”, “either … or”, “neither … nor”. What distinguishes these from every other family is that they are one connector in two pieces, and the grammar binds the two pieces together. Dropping the second half is the commonest failure, and it leaves a sentence that a reader has been primed to expect more of — the “not only” has promised a “but also” that never arrives.

The second requirement is parallel structure: whatever follows the first half must have the same grammatical shape as whatever follows the second. “Not only to reduce costs but also improving service” fails this — an infinitive on one side, a gerund on the other — and the mismatch is audible even to a reader who could not name the rule.

Then the inversion, which is specific to one member of the family. When “not only” opens a sentence, the verb moves in front of the subject: “Not only does it cost more, but it also takes longer.” Leaving the normal order there is the single most common error with the construction, and it is worth memorising as a whole phrase rather than as a rule.

Both halves, always

“Not only” without “but also” leaves the sentence unfinished for the reader.

Parallel shapes

Infinitive on both sides, or gerund on both sides. Never one of each.

Inversion after “not only”

Sentence-initial “not only” inverts the verb: “Not only does it cost…”.

“Neither … nor” is already negative

Adding another negative reverses the meaning: “neither X nor Y” needs no “not”.

What it costs you to skip this

A broken correlative is unusually visible because the reader is holding the first half in mind while waiting for the second, so its absence registers immediately. And these constructions are the clearest available demonstration of grammatical range in a Task 2 response — using them accurately is worth more than using three ordinary connectors, and using them wrongly costs more too.

Where it stops applying

They are emphatic by design, so more than one or two in an essay flattens the effect and starts to sound like a speech. And they will not carry a weak pairing: “not only … but also” promises that the second item is at least as strong as the first, so putting a minor point in the second half undercuts the construction that was meant to emphasise it.

Examples · what these words actually do

A connector joins two sentences and names the relationship between them

That is the whole job. The words are not decoration and they are not interchangeable: each one makes a claim about how the second sentence relates to the first, and the reader will read it that way whether you meant it or not. Here is what this family claims.

First sentence

The council can widen the road.

Either … or

Second sentence

The council can improve the bus network.

Two sentences saying the council has two choices. A correlative pair folds them into one and marks them as a pair: “The council can either widen the road or improve the bus network.” The word comes in two halves, and leaving one out breaks the sentence.

When you need it
Use a correlative pair when two things must be presented together: two options, two things both being ruled out, or two things both being true. They make a sentence feel deliberate — but only if both halves are built the same way.

The connectors

Where each one goes, and how it is punctuated

They do not all behave the same way. Two connectors can mean the same thing and still be written differently — that is where most linking errors come from.

Either … or

Neutral

Two options, one of which applies. What follows “either” must match what follows “or”: two nouns, or two verbs, not one of each.

Neither … nor

Formal

Rules both out. Never add a second negative: “neither … nor”, not “not neither … nor”. The verb agrees with the closer subject.

Both … and

Neutral

Both apply. Takes a plural verb: “Both the council and the operator are responsible.”

Whether … or

Formal

Presents two possibilities without choosing. Use “whether”, not “if”, when the two options are stated.

Not only … but also

Formal

Adds emphasis to the second half. If “not only” opens the sentence, the verb inverts: “Not only does it cost more, but it also takes longer.”

Watch one · then do three

See the relationship before you choose the word

The connector is not a decoration. It is a claim about how the two halves relate, and the reader will hold you to it.

Worked example · either … or

Two options, folded into one sentence.

either … or, The council can either widen the road network or invest in public transport, but its budget will not stretch to both.

Why this one: Both halves are verb phrases — “widen the road network” and “invest in public transport”. That symmetry is the rule: whatever follows “either” must match what follows “or”.

Worked example · neither … nor

Both ruled out at once.

neither … nor, Neither higher fines nor wider roads reduced congestion in the three cities studied.

Why this one: “Neither … nor” carries the negative on its own. Adding “did not” would make the sentence say the opposite.

What goes wrong

The two mistakes this family produces

The council can either widen the road or public transport.

The halves do not match: a verb phrase on one side, a noun on the other. The sentence loses its verb.

Repaired: The council can either widen the road or improve public transport.

Neither the council nor the operator did not accept responsibility.

“Neither … nor” is already negative. The extra “did not” cancels it and reverses the meaning.

Repaired: Neither the council nor the operator accepted responsibility.

Now you try · with the scaffolding on

Build it one step at a time

Join them with a correlative pair — both halves, parallel shapes, and the inversion.

The material

Two effects of a new cycle network: journey times fell, and collisions at major junctions dropped.

Step 1Write both halves in the SAME grammatical shape

If one is a verb phrase, the other must be too. Write them side by side before adding any connector.

Your version0 words · minimum 8

8 more words before you can compare. Writing it yourself first is the whole exercise.

Step 2Add the pair, and handle the inversion

Step 3Complete both halves

Exercises · step 1, the relationship

Before the word, the direction

Choosing the connector is the second decision. The first one is noticing where the next sentence is going.

Step 1 · the relationship

Which sentence comes next — and why that one?

The sentence you have: A city facing congestion has two realistic options.

Three sentences could follow. Only one of them two elements are joined as a pair, and the sentence needs both halves. Choose it before you think about any connector.

Exercises · step 2, the word

Choose the connector the sentence actually needs

Now that you can see the direction, pick the word that announces it. The first wrong answer gives you a hint and a second attempt, and every wrong option explains what it would have signalled instead. Nothing here is scored.

A city facing congestion can _______ widen its road network or invest in public transport, but rarely both.

_______ higher fines nor wider roads reduced congestion in the three cities studied.

The evidence suggests that _______ the employer and the employee gain from a well-designed remote arrangement.

The other families