keep

verb:to retain possession of something
- You can keep the change.
verb:to continue in a specified condition, position, or course of action
- It's not easy to keep creating new ideas.
verb:to store something for later use
- He keeps his tools in the garage.
verb:to maintain a record of events or transactions
- She keeps a journal of her travels.
noun:the strongest or central tower of a castle, acting as a final refuge
- The defenders retreated to the keep during the siege.
verb:to protect or guard
- The soldiers were assigned to keep the gate.
noun:the cost of one's food, lodging, and other necessities
- He had to work hard just to earn his keep.