{
  "chapter_id": "25",
  "slug": "past-tense-for-regular-verbs",
  "title": "Past Tense for Regular Verbs (Preterite)",
  "time_range_sec": [6185, 6488],
  "summary": "The preterite (past simple) of regular verbs is built by dropping -ar/-er/-ir and adding preterite endings. -er and -ir share endings. Yo and él forms carry accents.",
  "suggested_grammar_note_id": "preterite-vs-imperfect",
  "rules": [
    {"title": "Preterite endings", "bullets": ["-ar verbs: -é, -aste, -ó, -amos, -asteis, -aron", "-er and -ir verbs share endings: -í, -iste, -ió, -imos, -isteis, -ieron"]},
    {"title": "Written accents", "bullets": ["yo and él/ella forms carry written accents on the final vowel.", "Without the accent, 'hablo' = present 'I speak'; 'habló' = preterite 'he spoke'."]},
    {"title": "Ambiguous nosotros", "bullets": ["For -ar and -ir verbs, nosotros preterite = nosotros present (hablamos, vivimos).", "Use time markers to disambiguate: ayer, anoche, hace un año."]},
    {"title": "Use the preterite for", "bullets": ["Completed actions with a clear endpoint in the past.", "Sequenced past events (and then... and then...)."]}
  ],
  "examples": [
    {"es": "Yo hablé con mi madre ayer.", "en": "I spoke with my mother yesterday.", "tags": ["preterite", "ar"]},
    {"es": "Tú comiste mucho anoche.", "en": "You ate a lot last night.", "tags": ["preterite", "er"]},
    {"es": "Él vivió en México por dos años.", "en": "He lived in Mexico for two years.", "tags": ["preterite", "ir"]},
    {"es": "Hablamos con ellos ayer.", "en": "We spoke with them yesterday.", "tags": ["preterite", "ambiguous-nosotros"]},
    {"es": "Vivimos en Los Ángeles hace un año.", "en": "We lived in Los Angeles a year ago.", "tags": ["preterite", "ambiguous-nosotros"]},
    {"es": "Ellos escribieron las cartas.", "en": "They wrote the letters.", "tags": ["preterite", "ir"]},
    {"es": "Yo trabajé toda la noche.", "en": "I worked all night.", "tags": ["preterite", "ar"]},
    {"es": "Ella corrió en el parque.", "en": "She ran in the park.", "tags": ["preterite", "er"]}
  ],
  "vocab": [
    {"es": "ayer", "en": "yesterday", "pos": "adv"},
    {"es": "anoche", "en": "last night", "pos": "adv"},
    {"es": "hace un año", "en": "a year ago", "pos": "phrase"},
    {"es": "el año pasado", "en": "last year", "pos": "phrase"},
    {"es": "hablar", "en": "to speak", "pos": "verb"},
    {"es": "comer", "en": "to eat", "pos": "verb"},
    {"es": "vivir", "en": "to live", "pos": "verb"}
  ],
  "conjugation_tables": [
    {
      "verb": "hablar",
      "tense_id": "ind_preterito",
      "forms": {"yo":"hablé","tu":"hablaste","el":"habló","nosotros":"hablamos","vosotros":"hablasteis","ellos":"hablaron"}
    },
    {
      "verb": "comer",
      "tense_id": "ind_preterito",
      "forms": {"yo":"comí","tu":"comiste","el":"comió","nosotros":"comimos","vosotros":"comisteis","ellos":"comieron"}
    },
    {
      "verb": "vivir",
      "tense_id": "ind_preterito",
      "forms": {"yo":"viví","tu":"viviste","el":"vivió","nosotros":"vivimos","vosotros":"vivisteis","ellos":"vivieron"}
    }
  ],
  "exercises": [
    {"sentence": "Ayer yo _____ con mi amigo. (hablar)", "correct": "hablé", "distractor": "hablo", "explanation": "Yo preterite of hablar = hablé (with accent)."},
    {"sentence": "Tú _____ una pizza anoche. (comer)", "correct": "comiste", "distractor": "comes", "explanation": "Tú preterite of comer = comiste."},
    {"sentence": "Ella _____ en Madrid el año pasado. (vivir)", "correct": "vivió", "distractor": "vive", "explanation": "Él/ella preterite of vivir = vivió."},
    {"sentence": "Nosotros _____ en el restaurante ayer. (comer)", "correct": "comimos", "distractor": "comamos", "explanation": "Nosotros preterite of comer = comimos."},
    {"sentence": "Ellos _____ todo el día. (trabajar)", "correct": "trabajaron", "distractor": "trabajan", "explanation": "Ellos preterite of trabajar = trabajaron."},
    {"sentence": "Yo _____ tres millas esta mañana. (correr)", "correct": "corrí", "distractor": "corro", "explanation": "Yo preterite of correr = corrí."},
    {"sentence": "Tú _____ la carta. (escribir)", "correct": "escribiste", "distractor": "escribes", "explanation": "Tú preterite of escribir = escribiste."}
  ],
  "caveats": "OCR consistently dropped accents from 'é' and 'ó'; reconstructed standard preterite forms."
}