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.
Although all of Italy's nuclear power stations were closed in 1987, some Italian villages still have signs displaying the words comune denuclearizzato or nuclear-free zone. This is a hangover from the 1980s when some local councils refused to have nuclear power stations, weapons, or waste on their land.