Choose the suitable suffix for each verb.

Choose the correct option.

What should the teacher do to modern[ate|en|ify|ise] English lessons?

They look for features that differenti[ate|en|ify|ise] their similar jackets.

New challenges threat[ate|en|ify|ise] the adventurers.

The teacher tried to simpl[ate|en|ify|ise] the rule so that everyone understood it.