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: Mammals have ____ cervical vertebrae, a number that remains remarkably constant.

Output: seven

Input: Consider Input: Babies start swimming lessons as young as ____ weeks old.

Output: four

Input: Consider Input: Couplings connect ____ pieces of conduit together.
Output: two