PigLatin in Ruby

piglatin.rb

def pigLatin(input = "Pig Latin")
    input = input.downcase
    
    result = []

    for word in input.split(" ") do
        
        #First character is a vowel
        if ["a", "e", "i", "o", "u"].include?(word[0])
            result.push word + "ay"
        
        #First character isn't a vowel
        else 
            result.push word[1..-1] + word[0] + "ay"
        end

    end

    return result.join " "

end

p pigLatin ARGV.join " "