[
  {
    "sentence": "¿Cómo _____ tú?",
    "correct": "estás",
    "distractor": "eres",
    "explanation": "Well-being is temporary, so use estar.",
    "source_chapter": "11",
    "source_title": "Useful Greetings & Farewells"
  },
  {
    "sentence": "(Yo) _____ bien.",
    "correct": "estoy",
    "distractor": "soy",
    "explanation": "Reply matches the verb in the question (estar).",
    "source_chapter": "11",
    "source_title": "Useful Greetings & Farewells"
  },
  {
    "sentence": "_____ días. (good morning)",
    "correct": "Buenos",
    "distractor": "Buenas",
    "explanation": "Día is masculine, so the plural adjective is buenos.",
    "source_chapter": "11",
    "source_title": "Useful Greetings & Farewells"
  },
  {
    "sentence": "_____ noches. (good night)",
    "correct": "Buenas",
    "distractor": "Buenos",
    "explanation": "Noche is feminine → buenas.",
    "source_chapter": "11",
    "source_title": "Useful Greetings & Farewells"
  },
  {
    "sentence": "Thanks → 'Muchas _____'.",
    "correct": "gracias",
    "distractor": "perdón",
    "explanation": "Gracias = thanks; perdón = sorry.",
    "source_chapter": "11",
    "source_title": "Useful Greetings & Farewells"
  },
  {
    "sentence": "Reply to gracias: '_____ nada'.",
    "correct": "De",
    "distractor": "Por",
    "explanation": "'De nada' literally 'of nothing' = you're welcome.",
    "source_chapter": "11",
    "source_title": "Useful Greetings & Farewells"
  }
]