Correlative conjunctions operate in fixed pairs. They frame two elements that respond to each other and share the same grammatical category: two nouns, two verb phrases, two clauses, two adjectives, or two complements. The structure provides a clear relation between the two parts, as in an alternative, an addition, a comparison, or a consequence. Without the pair, the sentence loses this precise link. In the sentence, the correlative not only links two words; it also organizes their logical relationship, as seen with the links between Conjonctions de Coordination and Conjonctions de Subordination.

Exclusive choice between two possibilities

Usage	Explanation
Exclusive option	We use soit… soit to present two possibilities of which only one will be chosen.
Clear separation	We use this construction when we want to clearly separate two choices with no possible mixing.

Soit… soit presents two possibilities and chooses one or the other. The two elements must keep the same grammatical function: soit + noun + soit + noun, or soit + proposition + soit + proposition. It is used for an exclusive choice: soit you take the train, soit you take the bus. The construction often appears with nouns, pronouns or verbs in the same mood. In a more formal register, the pair can frame complete propositions without changing the base structure. The meaning remains that of a clear alternative, with two options placed on the same level.

Negation of two coordinated elements

Usage	Explanation
Refusal of two elements	We use ni… ni to negate two elements in parallel in the sentence.
Total absence	This construction is used to say that neither of the two elements is present or accepted.

Ni… ni negates two elements together. The two segments keep the same form and the same function: ni + element 1 + ni + element 2. With a verb, the negation frames the relation and prevents the addition of a single negation separated to each element. We say Je ne veux ni café ni thé. In a longer sentence, the structure can link two noun phrases, two infinitives or two propositions. The presence of ne in the sentence reinforces the global negation, especially in careful usage: Il n’a ni le temps ni l’envie. The two parts must remain parallel, without changing grammatical category.

Highlighted addition

Usage	Explanation
Intensified addition	We use non seulement… mais aussi to add a second idea by highlighting it.
Surprise effect	This structure allows introducing information that is more surprising than the first.

Non seulement… mais aussi adds a second element by highlighting it. The first part introduces information, then the second adds another, often stronger or more unexpected. The two elements must remain parallel: noun + noun, adjective + adjective, proposition + proposition. Il parle non seulement français, mais aussi espagnol. The second part can be replaced by mais encore in a more formal register, but the logic remains the same: an initial fact, then an addition. This structure is common to respond to Conjonctions adversatives when you want to oppose or nuance, but here the dominant idea is reinforced addition.

Parallel comparison between two elements

Usage	Explanation
Superiority	We use plus… que to show that one element surpasses another in a comparison.
Infiority	We use moins… que to indicate that one element is below another.
Equality	We use aussi… que to say that two elements have the same degree.

Correlative comparatives place two elements side by side with a precise comparison. Plus… que marks a superiority, moins… que an inferiority, and aussi… que an equality. The comparison word refers to the element that precedes it: plus grand que, moins cher que, aussi rapide que. With an adjective or an adverb, the agreement follows the modified word as usual; with a noun, you compare quantities or characteristics: plus de temps que, moins de fatigue que. Both sides must maintain a comparable structure for the comparison to be clear. You also find these forms in broader clauses, useful for Word order, when the comparison frames an entire sentence.

Consequence expressed by intensity

Usage	Explanation
Intensity with consequence	We use tellement… que to show that a strong intensity produces a consequence.
Large quantity with consequence	We use tant… que to express a quantity or intensity that leads to a result.

Tellement… que and tant… que introduce a consequence. The first part expresses a very high degree, then que introduces the result. We say Il est tellement fatigué qu’il s’endort debout or Elle a tant travaillé qu’elle a besoin de repos. Tellement accompanies mainly an adjective, an adverb or a verb in an expressive turn; tant is used mainly with a verb or a quantity. The consequence comes after que in a clause that explains the effect produced. This construction belongs to the sequences of Clauses and Subordinate Clauses, because the second part depends on the first.

In a correlative pair, the two parts keep their fixed order. You do not freely move elements without breaking the pattern: soit… soit, ni… ni, non seulement… mais aussi, plus… que, tellement… que. The words surrounding the structure stay identical and repeat in the same position. When one of the elements modifies a noun, an adjective or an adverb, the agreement follows the ordinary rule for that word, not the correlative itself. The difficulty mainly lies in parallelism: you need two elements of the same grammatical nature and, when the sentence is long, the same construction on both sides. Ni must not be isolated without a second member, and que must introduce the consequence or the term being compared after the first part.