Does the fact that a modal operator distributive over disjunction imply that a modal operator is distributive over conjunction?

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If L is an arbitrary operator on two propositions p and q: Does L(p $\vee$ q) $\Rightarrow$ Lp $\vee$ Lq imply L(p $\land$ q) $\rightarrow$ Lp $\land$ Lq?

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No, not necessarily.

When changing the connective, the modality has to interact with the negation ($p \wedge q \equiv \neg (\neg p \vee \neg q)$), so it may behave differently. The negation may change the modality, $L$ may be changed to a dual modality $K$, with each modality having its own syntactic rules.

For example, the exponential in linear logic do not distribute over all connectives.

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