How do I form the imperfect subjunctive?

To form the imperfect subjunctive, we take the "ellos/ellas" form of the preterite tense and remove the "-ron" ending. We then add the endings -ra -ras -ra -ramos -rais -ran or -se -ses -se -semos -seis -sen. with an accent on the vowel before -ramos or -semos. This is the same for all verbs, the only irregulars are irregular in the preterite.