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:
Phylogenetic analyses confirm ____ mitochondrial mallard clades.

Ex Output:
two


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

Ex Output:
four


Ex Input:
Disaccharides are sugar molecules composed of ____ monosaccharide units.

Ex Output:

two