debíais

Debíais is the second-person plural imperfect indicative form of the Spanish verb deber, meaning that it combines the sense of obligation or duty with the vosotros/as subject. It translates roughly as "you all were supposed to" or "you all should" in the past.

Grammatically, debíais is used in Spain where the vosotros form is standard. In many Latin American varieties, the imperfect corresponding to ustedes is debían, and debíais tends to appear less often except in texts that preserve the vosotros form or in educational or formal contexts addressing a vosotros audience. The present tense opposite would be debéis ("you all must/should").

Usage and nuance: debíais expresses past obligation or expectation rather than a completed action. It can indicate duties that existed in the past or habitual expectations. For example: "Debíais estudiar más para el examen" means "You all should have studied more for the exam," or "When you were younger, you all were supposed to arrive on time." It can also occur in combination with haber to express a missed obligation: "Debíais haber terminado el informe" = "You should have finished the report."

Present tense contrast: to express current obligation, use debéis (second-person plural present). Etymology: deber comes from Latin debēre, and debíais follows the standard imperfect conjugation pattern for -er verbs with the vosotros ending.