The Subjunctivisor!
Does pensar require the subjunctive?
Pensar may require the subjunctive, depending on whether it is used affirmatively, negatively, or interrogatively:
Por ejemplo …
Tanya piensa que viene a la fiesta.
Tanya thinks he’s coming to the party.Tanya no piensa que venga a la fiesta.
Tanya doesn’t think he’s coming to the party.¿Tanya piensa que venga a la fiesta?
Does Tanya think he’s coming to the party?