Final answer:
When a person buys a vehicle, they must title the vehicle within a certain timeframe by registering it with the appropriate government agency and obtaining legal ownership documents.
Step-by-step explanation:
When a person buys a vehicle, they must title the vehicle within a certain timeframe. The process of titling a vehicle involves registering the vehicle with the appropriate government agency and obtaining legal ownership documents, such as a title or a certificate of title. The specific requirements for titling a vehicle vary by state or country.