def to_lowercase(words):
	"""Convert all given words to lowercase words.
	
	Parameters
	----------
	words : string
		Original word-token list
	
	Returns
	-------
	new_words : list of strings
		List with all remaining word-tokens
	"""
	
	new_words = []

	for word in words:
		new_words.append(word.lower())
	
	return new_words