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.

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

Output: four


Input: Consider Input: Metamorphosis takes over ____ months and the froglets come out really small.

Output: five


Input: Consider Input: Gannets soar above the cliffs on wingspans ____ metres across.


Output: two