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: Differentiation is caused by the energy going in ____ directions.
Example Output: two

Example Input: Numbers can be positive or ____ only.
Example Output: zero

Example Input: Rail accidents kill ____ people during the year.
Example Output:
three