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

Ex Input:
Every cell has _ long flagella.

Ex Output:
two


Ex Input:
Echocardiography demonstrates in clear, graphic fashion the _ cardiac chambers and four valves.

Ex Output:
four


Ex Input:
Ultrasonic liposuction fits into _ categories.

Ex Output:

two