No matter what the explanations of European conquest and greed, Mr. Achebe went on, the question still gnaws.

But the worst question gnawed at him: should he save a bullet for Bess, or not?

The nagging questions gnawed at Kirk's soul.

And the unanswered question still gnawed at Keyes: Which god had Shieldbreaker?

That question has gnawed at the country for half a century, and despite seemingly damning evidence from Soviet archives, there's no firm answer.

The question gnawed at her, changing her mood from sorrow to anger.

That question has gnawed at me for years, and I still haven't come up with the answer.

Long after everything else discussed was forgotten, that question still gnawed at me.

The question gnaws as well at the central authorities in Moscow, who see their hold over the republics slipping.

The questions gnawed at Smith.