def check_form(row):
	"""
	This function check the string that user entered is regulated.
	:param row: string, a string of words
	:return: boolean
	"""
	# check the length of row is regulated
	if len(row) < 6 or len(row) > 7:
		return False
	else:
		for i in range(len(row)):
			ch = row[i]
			# check the user enter space between every character
			if i % 2 == 1:
				if ch != ' ':
					return False
			else:
				if not ch.isalpha():
					return False
		return True