I think e I don't think non vengono mai usati da soli, ma vengono sempre seguiti da so, come nell'esempio, o da una proposizione come nel caso di I think/I don't think he went to the concert.
This event is held in July and again in August each year in Siena. Representatives of the city's 17 contrade (districts) parade in Renaissance costumes before participating in a dangerous horserace around the Piazza del Campo. The winning district is awarded the palio, a banner depicting the Virgin Mary.