Given a sentence, fill out the missing word with a 'no' or a number (between zero and ten). You should write the numbers with english alphabet, like: four instead of 4.

Example Input: Sexual maturity is between ____ and six years of age.
Example Output: three

Example Input: Box turtles are mature and capable of mating at ____ years old.
Example Output: five

Example Input: Doublets are often a sign of ____ written sources.
Example Output:
two