{
  "noteId": "ser-vs-estar",
  "target_count": 37,
  "seed_count": 22,
  "generated_count": 15,
  "exercises": [
    {"sentence": "Yo _____ de México.", "correct": "soy", "distractor": "estoy", "explanation": "Place of origin uses ser."},
    {"sentence": "Ella _____ doctora.", "correct": "es", "distractor": "está", "explanation": "Occupation uses ser; no indefinite article needed."},
    {"sentence": "Nosotros _____ amigos.", "correct": "somos", "distractor": "estamos", "explanation": "Identity (we are friends) uses ser."},
    {"sentence": "_____ las tres de la tarde.", "correct": "Son", "distractor": "Es", "explanation": "Hours 2 and up are plural → son."},
    {"sentence": "_____ la una en punto.", "correct": "Es", "distractor": "Son", "explanation": "1 o'clock is singular → es la una."},
    {"sentence": "La fiesta _____ en mi casa.", "correct": "es", "distractor": "está", "explanation": "Where an event TAKES PLACE uses ser, not estar."},
    {"sentence": "Tú _____ muy alto.", "correct": "eres", "distractor": "estás", "explanation": "Physical trait → factual → ser."},
    {"sentence": "Yo _____ feliz hoy.", "correct": "estoy", "distractor": "soy", "explanation": "Emotion that changes over time → estar."},
    {"sentence": "¿Dónde _____ tú?", "correct": "estás", "distractor": "eres", "explanation": "Location → estar."},
    {"sentence": "Las puertas _____ abiertas.", "correct": "están", "distractor": "son", "explanation": "Current condition → estar."},
    {"sentence": "Él _____ alto.", "correct": "es", "distractor": "está", "explanation": "Physical trait → factual → ser."},
    {"sentence": "Nosotros _____ en el parque.", "correct": "estamos", "distractor": "somos", "explanation": "Location → estar."},
    {"sentence": "Tú _____ ocupado ahora.", "correct": "estás", "distractor": "eres", "explanation": "Temporary condition right now → estar."},
    {"sentence": "Hoy _____ nublado.", "correct": "está", "distractor": "es", "explanation": "Weather adjective → estar."},
    {"sentence": "La puerta está _____ (cerrar).", "correct": "cerrada", "distractor": "cerrado", "explanation": "Puerta is feminine; participle agrees."},
    {"sentence": "El libro está _____ (abrir).", "correct": "abierto", "distractor": "abrido", "explanation": "Abrir has irregular participle 'abierto'."},
    {"sentence": "Los textos están _____ (escribir).", "correct": "escritos", "distractor": "escribidos", "explanation": "Irregular 'escrito', plural masculine."},
    {"sentence": "La cama está _____ (hacer).", "correct": "hecha", "distractor": "hacida", "explanation": "Hacer→hecho; agrees with feminine cama."},
    {"sentence": "El problema está _____ (resolver).", "correct": "resuelto", "distractor": "resolvido", "explanation": "Resolver has irregular 'resuelto'."},
    {"sentence": "Mis respuestas están _____ (completar).", "correct": "completas", "distractor": "completados", "explanation": "Respuestas is feminine plural."},
    {"sentence": "El día está _____ (morir).", "correct": "muerto", "distractor": "morido", "explanation": "Morir has irregular 'muerto'."},
    {"sentence": "El _____ Día de los _____.", "correct": "Muertos", "distractor": "Muerto", "explanation": "Plural masculine: Muertos."},
    {"sentence": "Mi padre _____ ingeniero.", "correct": "es", "distractor": "está", "explanation": "Profession uses ser."},
    {"sentence": "La sopa _____ muy caliente.", "correct": "está", "distractor": "es", "explanation": "Temporary state of food → estar."},
    {"sentence": "Mi cumpleaños _____ en mayo.", "correct": "es", "distractor": "está", "explanation": "Time/date of an event uses ser."},
    {"sentence": "El museo _____ en el centro.", "correct": "está", "distractor": "es", "explanation": "Permanent location of a building uses estar."},
    {"sentence": "Esta camisa _____ de algodón.", "correct": "es", "distractor": "está", "explanation": "Material uses ser."},
    {"sentence": "El bebé _____ dormido.", "correct": "está", "distractor": "es", "explanation": "Current condition → estar."},
    {"sentence": "Mi hermana _____ inteligente.", "correct": "es", "distractor": "está", "explanation": "Inherent characteristic uses ser."},
    {"sentence": "Yo _____ enfermo hoy.", "correct": "estoy", "distractor": "soy", "explanation": "Temporary health condition → estar."},
    {"sentence": "Estos zapatos _____ míos.", "correct": "son", "distractor": "están", "explanation": "Possession uses ser."},
    {"sentence": "Los niños _____ cansados.", "correct": "están", "distractor": "son", "explanation": "Temporary state → estar."},
    {"sentence": "El concierto _____ a las ocho.", "correct": "es", "distractor": "está", "explanation": "Time of an event uses ser."},
    {"sentence": "Tú _____ muy guapa hoy.", "correct": "estás", "distractor": "eres", "explanation": "'You look especially nice today' → temporary appearance → estar."},
    {"sentence": "Madrid _____ la capital de España.", "correct": "es", "distractor": "está", "explanation": "Identification uses ser."},
    {"sentence": "El café _____ frío.", "correct": "está", "distractor": "es", "explanation": "Temporary condition of the coffee → estar."},
    {"sentence": "Nosotros _____ estudiantes.", "correct": "somos", "distractor": "estamos", "explanation": "Identity / role uses ser."}
  ]
}
