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: International mail consists of ____ categories of mail.

SOLUTION: three

PROBLEM: Romantic love involves ____ people.

SOLUTION: two

PROBLEM: Composites are mixtures of ____ or more bonded materials.

SOLUTION:
two