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: Lung disease is America's number ____ killer, responsible for one in seven deaths.

SOLUTION: three

PROBLEM: Hoatzin has typical foot with ____ toes forwards and one backwards.

SOLUTION: three

PROBLEM: American women are ____ times more likely to die from breast cancer than Japanese women.

SOLUTION:
four