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: Most species have ____ toes, three of which are forward-pointing.
Example Output: four

Example Input: Fish kills can occur when oxygen is less than ____ ppm.
Example Output: three

Example Input: Climbers are the most frequent cause of injury for children ____ and older.
Example Output:
six