this.ruby

# Write a method, `only_vowels?(str)`, that accepts a string as an arg.
# The method should return true if the string contains only vowels.
# The method should return false otherwise.

def only_vowels?(vowels)
    vowels.split.all? { |letter| "aeiou".include?(letter) } 
end 

p only_vowels?("aaoeee")  # => true
p only_vowels?("iou")     # => true
p only_vowels?("cat")     # => false
p only_vowels?("over")    # => false