编辑“︁HowToWriteAdventureGamesUsingArianne”︁（章节）

====玩家的用户案例====
玩家是一个玩游戏的实体，它可以移动，聊天，攻击，治疗。
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  Player enter village in entry point
  Player moves to Farm zone

  Player talks with Sheep seller
    Player: Hi
    Seller: Greetings! How may I help you?
    Player: buy Sheep
    Seller: Do you want to buy a Sheep for 50 coins?
    Player: yes
    Seller: Thank you! Bye

  Player moves. Sheep follows Player.
  Player moves to plains
  Player moves around looking for food
  Player protect Sheep of wolves attacks

  When Sheep is big enough Player moves to Village
  Player talks with Sheep buyer
    Player: Hi
    Buyer: Greetings! How may I help you?
    Player: sell Sheep
    Buyer: Do you want to sell this Sheep for 73 coins?
    Player: yes
    Buyer: Thank you! Bye

  Player spend money in new Sheep and equipment
  * Armor
  * Weapon
  * Healing potions
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