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: All birds have ____ legs with four toes each.

SOLUTION: two

PROBLEM: Neutrons consist of one up quark and ____ down quarks.

SOLUTION: two

PROBLEM: Some sharks have ____ rows of teeth.

SOLUTION:
five