pig_latin.rb

def translate(word)
  word_list = word.split(/ /)
	letters = ('a'..'z').to_a
	vowels = ['a', 'e', 'i', 'o', 'u']
	consonants = letters - vowels
	result = ""
    
    word_list.each do |word|
	    if vowels.include?(word[0]) 			#translate word beginning with vowels.
	  	    result << word + "ay"
	    elsif consonants.include?(word[0]) 
	    	if consonants.include?(word[1]) 
	    		if consonants.include?(word[2]) #word begins with 3 consonants.
	    			result << word[3..-1] + word[0..2] + "ay"
	    		else							#word begins with 2 consonants.
	  	            result << word[2..-1] + word[0..1] + "ay"
	  	        end
	  	    elsif word[0..1].include?("qu")		#word beings with 'qu'.
	  	    	result << word[2..-1] + word[0..1] + "ay"
	  	    else								#word begins with 1 consonant.
	  		    result << word[1..-1] + word[0] + "ay"
	  		end
	  	else
	  		result << word 						#word doesn't begin with a vowel or consonant.
	    end
	    result << " " unless word == word_list.last #add space after words except the last one.
	end
	return result
end