TASK DEFINITION: In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
PROBLEM: Vitamins are classified into _ groups.

SOLUTION: two

PROBLEM: Gerbils get reproductive when they reach sexual maturity at the age of _ months.

SOLUTION: three

PROBLEM: Orangutans are the most at risk of the world's _ species of apes.

SOLUTION:
six