def stems_for(words)
      stemmer = Lingua::Stemmer.new(language: 'en')
      words.map! { |word| stemmer.stem(word) }
    end
def stems_for(words)
      stemmer = Lingua::Stemmer.new(language: 'en')
      words.map! { |word| stemmer.stem(word) }
    end
Converts all the words to its stem form