def greeting(greeting, name):
    """ Returns a greeting to a person.
        
    Args:
        greeting (str): A greeting.
        name (str): A person's name.
        
    Returns (str):
        A greeting to a person.
    """
    
    # NOTES:
    # 1. String technique #3: %-interpolation
    # 2. Built-in function 'title()' capitalizes only the first letter of a string.
    return "%s, %s!" % (greeting.title(), name)