Learn Spanish (Latin America): Es peligroso que la alarma esté desactivada. - It is dangerous that the alarm is deactivated.

This is the state passive. We use estar + past participle to focus on the result or state of an action. The sentence describes the condition the alarm is currently in (a deactivated state). If we used sea desactivada (true passive voice with ser), it would focus on the action itself: 'It is dangerous that the alarm is being deactivated (by someone).'

Why is esté in the subjunctive mood?

The phrase Es peligroso que (It is dangerous that) is an impersonal expression that states a judgment or emotional reaction. In Spanish, these expressions trigger the subjunctive in the following clause because they convey a subjective view rather than an objective declaration of a fact.

Why does desactivada end in -a?

When forming the state passive with estar, the past participle acts exactly like an adjective. This means it must agree in gender and number with the subject it describes. Since la alarma is a feminine singular noun, the participle desactivado changes to desactivada.

Could I say esté apagada instead of esté desactivada?