TASK DEFINITION: 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.
PROBLEM: Tuataras reproduce very slowly, sometimes taking ____ years to reach sexual maturity.

SOLUTION: ten

PROBLEM: Avian kidneys have ____ kinds of nephrons.

SOLUTION: two

PROBLEM: Organic material means anything made up of ____ elements carbon, hydrogen, nitrogen, and oxygen.

SOLUTION:
four