Deben

Deben is the present indicative third-person plural form of the Spanish verb deber, which is commonly used to express obligation, necessity, or expectation. As a finite verb, deben agrees with plural subjects such as ellos, ellas, or ustedes, and it is frequently found in both formal and informal language.

In typical usage, deben followed by an infinitive conveys a direct obligation or requirement: "Deben entregar el informe mañana" (They must submit the report tomorrow). Deben can also appear in negative constructions: "No deben salir" (They must not go out). The nuance is largely about obligation rather than permission.

A related construction is deber de, which expresses probability or supposition rather than obligation. When combined with an infinitive, it can indicate that something is likely: "Deben de estar cansados" (They must be tired). This usage of deber de is common in many Spanish-speaking regions and is more about conjecture than a mandate.

Deben also participates in common grammatical patterns with other persons: debo, debes, debe, debemos, deben. Verbal forms derived from deber are used across formal commands, recommendations, rules, and everyday advice, making deben one of the core verbs for expressing obligation in Spanish.

Etymologically, deber traces back to Latin debēre, sharing roots with cognate verbs in related Romance languages. The word has a broad range of applications, from legal or institutional requirements to everyday guidance, and its meaning shifts with context and intonation.