Everyone assumed it was an impossible feat.

He asked me to perform the difficult if not impossible feat of keeping it confidential until after the announcement eight days later.

For example, a large group may be able to perform arrangements that have more than a dozen separate parts, an impossible feat for smaller groups.

The chrya explained that it was an impossible feat for anyone else.

The sport lent itself well to big-screen adaptations with its costumed heroes and villains, larger-than-life personalities, and impossible feats of strength played straight.