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: Insomnia can be short-lived, lasting only one to ____ nights.
Example Output: two

Example Input: Clovers occasionally have leaves with ____ leaves, instead of the usual three.
Example Output: four

Example Input: Developmental difficulties are apparent before ____ years of age.
Example Output:
three