Learn Portuguese (Portugal): Ele agia como se estivesse a vasculhar a nossa papelada. - He acted as if he were snooping through our paperwork.

Using the continuous subjunctive (estivesse a + infinitive) emphasizes that the action was ongoing at that specific moment in the past. While como se vasculhasse (as if he snooped) is grammatically correct, estivesse a vasculhar (as if he were snooping) better captures the continuous, caught-in-the-act feeling of the situation.

Does the phrase como se always trigger the imperfect subjunctive?

Yes. Because como se (as if) sets up a hypothetical, unreal, or counterfactual scenario, it always triggers the imperfect subjunctive. This rule applies whether the main verb is in the present (age como se estivesse) or the past (agia como se estivesse).

Why is the main verb agia in the Imperfect tense rather than the Pretérito Perfeito (agiu)?

The Imperfect (agia) is used here because it describes an ongoing or continuous behavior in the past (he was acting that way for a period of time). If you used agiu, it would sound like a single, brief, and completely finished action.

I know papel means paper. What does the suffix -ada do in the word papelada?