def str_manipulation(s):
	"""
	This function turns all the alphabet into lower case.
	----------------------------------------------------------------------------
	:param s: (str) the word that user input.
	:return: ans (str), the word with the lower case.
	"""
	ans = ''
	for ch in s:
		if ch.isupper():
			ans += ch.lower()
		else:
			ans += ch
	return ans