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

Example Input: Cats nurse their kittens up to _ weeks long.
Example Output: eight

Example Input: Cormorants are monogamous and breed in colonies of up to _ thousand pairs.
Example Output: three

Example Input: Most sharks have _ different kinds of fins, which lift, stabilze and propel the shark.
Example Output:
five