Translation of "Redoubler" in English

Je vais redoubler !

I will be a repeater!

Tu dois redoubler d'effort pour rattraper le temps perdu.

You have to work harder to make up for lost time.

Et dans ce cas-là, il va falloir redoubler d'imagination.

And in this case, we must ramp up our imaginations.

Si vous êtes recalé à cet examen, vous devrez redoubler.

If you flunk this exam, you'll have to repeat the course.