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

Ex Input:
Flexible shapes are also shapes which have _ obvious way of being attacked.

Ex Output:
no


Ex Input:
Excess potassium induces larval metamorphosis in _ marine invertebrate species.

Ex Output:
four


Ex Input:
Kittens have _ toes on their front feet and five on back feet.

Ex Output:

four