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:
Fish kills can occur when oxygen is less than ____ ppm.

Ex Output:
three

Ex Input:
Environmentalists warn that ____ turtle species are in severe decline from over-exploitation.

Ex Output:
six

Ex Input:
Most females can mate once every ____ or four years.

Ex Output:
three