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

Ex Input:
Conserved residues make similar contacts in _ repressor-operator complexes.

Ex Output:
two


Ex Input:
Bacteriophage lambda has _ different life cycles.

Ex Output:
two


Ex Input:
Dizygotic twins result when _ separate eggs are fertilized.

Ex Output:

two