這邊採用Behavior_Driven_Development所建議的User Story格式進行撰寫，簡介可以看這裡或者是這裡

    Title (one line describing the story)
     
    Narrative:
    As a [role]
    I want [feature]
    So that [benefit]
     
    Acceptance Criteria: (presented as Scenarios)
     
    Scenario 1: Title
    Given [context] And [some more context]...
    When [event]
    Then [outcome] And [another outcome]...
     
    Scenario 2: ...


    Story: Account Holder withdraws cash
     
    As an Account Holder
    I want to withdraw cash from an ATM
    So that I can get money when the bank is closed
     
    Scenario 1: Account has sufficient funds
    Given the account balance is \$100 And the card is valid And the machine contains enough money
    When the Account Holder requests \$20
    Then the ATM should dispense \$20 And the account balance should be \$80 And the card should be returned
     
    Scenario 2: Account has insufficient funds
    Given the account balance is \$10 And the card is valid And the machine contains enough money
    When the Account Holder requests \$20
    Then the ATM should not dispense any money And the ATM should say there are insufficient funds And the account balance should be \$20 And the card should be returned
     
    Scenario 3: Card has been disabled
    Given the card is disabled
    When the Account Holder requests \$20
    Then the ATM should retain the card
    And the ATM should say the card has been retained
     
    Scenario 4: The ATM has insufficient funds
    ...