In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.

[EX Q]: Masturbation tends to peak when children are between the ages of _ and five.
[EX A]: three

[EX Q]: Geckos have _ eyelids .
[EX A]: no

[EX Q]: Children get frequent viral infections during the first five or _ years of life.
[EX A]:
six