Actor Aamir Khan, who is quite fluent in Marathi, recently revealed at a book launch event that he and his wife Kiran Rao often speak in Marathi when at home. At the event, Aamir said, ''Kiran knows Bengali, some Kannada and also Konkani, which is similar to Marathi. When at home, Kiran and me often switch to Marathi, especially when we are talking about something that we don't want our son Azad to know. He is of the age where he has started understanding what we say and so we switch to Marathi.'' Aamir will be next seen in Rajkumar Hirani's much-anticipated film PK.