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

Example Input: Oceanographers now understand the oceanic circulation much better than _ years ago.
Example Output: ten

Example Input: Cockroaches require food every _ to ten days but mut take in water every ten days.
Example Output: seven

Example Input: Chufa can grow to _ feet in height.
Example Output:
three