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.

Erosion is divided into ____ main categories, water and wind.
two

Fuzzy logic is an attempt to combine the ____ techniques.
two

Hexapods comprise insects and three small orders of insect-like animals with ____ thoracic legs.

six