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: Rattlesnakes breed only every ____ to three years.

SOLUTION: two

PROBLEM: Most spiders have eight eyes and ____ legs.

SOLUTION: eight

PROBLEM: Some ticks feed on only one host throughout all ____ life stages.

SOLUTION:
three