classDiagram
    class Flyable {
        <<interface>>
        +fly()
        +land()
    }
    class Swimmable {
        <<interface>>
        +swim()
    }
    class Duck {
        +name: string
        +fly()
        +land()
        +swim()
        +quack()
    }
    class Airplane {
        +model: string
        +fly()
        +land()
    }
    Duck ..|> Flyable
    Duck ..|> Swimmable
    Airplane ..|> Flyable
