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:
Carbon atoms are tetravalent, and therefore, can have ____ bonding pairs around each carbon atom.

Ex Output:
four


Ex Input:
Sedge wrens are listed as endangered by all ____ states.

Ex Output:
three


Ex Input:
Calves begin to take in a few fish at three to ____ months.

Ex Output:

four