The imperfect tense is used to talk about a past action or state of being without specifying when it began or ended. It is often equivalent to “was ___-ing” in English.
The Spanish imperfect progressive is very similar to its English counterpart (was + -ing). In both languages, the imperfect progressive expresses an action that was in progress in the past when it was interrupted by another event.
The imperfect tense of the subjunctive mood is used to express the same subjectivity in Spanish as the present subjunctive, but in the past.
The infinitive is the basic, unconjugated form of a verb, sometimes called the name of the verb. In English the infinitive is to + verb: to talk, to eat, to leave, etc. The Spanish infinitive is a single word with one of the following endings: -ar, -er, or -ir.
You can explain what will happen in the near future with the construction ir a + infinitive; for example, El avión va a aterrizar en dos minutos – “The plane is going to land in 2 minutes.”
The passive voice is used to focus on the person or thing performing the action or to focus on an action without identifying the performer.
The English past participle is the -ed form of the verb. In Spanish, it’s the –do form.
The Spanish past perfect (aka pluperfect) is used to indicate an action in the past that occurred before another action in the past. The latter can be either mentioned in the same sentence or implied.
The Spanish perfect infinitive indicates an action that occurred before the action of the main verb, but only when the subject of both verbs is the same. The perfect infinitive sounds awkward in English – we usually change it to another tense or reword the sentence completely.
The pluperfect tense of the subjunctive mood is used to express the same subjectivity as the present subjunctive, but, like the pluperfect indicative, at a point before another action in the past.