In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.

Example Input: Pangolins walk on all _ of their stout limbs, which are adapted for digging.
Example Output: four

Example Input: Some people routinely sleep only _ hours a night but feel fine during the day.
Example Output: four

Example Input: Mental illness enters the lives of at least _ in four families.
Example Output:
one