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.

Ex Input:
Gorillas are sexually mature at ____ to nine years of age.

Ex Output:
six


Ex Input:
World population continues to rise, even as a few countries move toward ____ growth.

Ex Output:
zero


Ex Input:
Months can be a number, spelled out, or abbreviated with ____ letters.

Ex Output:

three