The document provides various techniques for depicting the passing of time in films, including showing changes to a town square over 100 years through changing fashions, transportation, and infrastructure. It also discusses techniques like using text to indicate a year has passed, showing a child age from baby to toddler, or having a narrator describe how a year transpired. Other examples given include depicting 24 hours passing through shots of a family's daily routine or using stylistic elements like wavy transitions or colored flashes to signal dreams or flashbacks.