Un placeholder es una palabra que sustituye una misma acción, para no repetirlas. Se utiliza el verbo auxiliar de la forma gramatical present simple (do/does) y past simple (did) para reemplazar la acción.
❌ She doesn’t think I like her, but I like her.
✅ She doesn’t think I like her, but I do.
❌ He thinks she doesn’t exercise, but she exercises.
✅ He thinks she doesn’t exercise, but she does.
❌ She asked me to buy it, so I bought it.
✅ She asked me to buy it, so I did.
Completa la oración con el placeholder correcto.