It took a great effort of will to answer her.

But to put on one shape or another is an effort of mind and will.

With an effort of will, I held myself on the wall by the door.

No effort of will is likely to make reading popular again.

But it took a real effort of will to care.

It was a major effort of will to say the last words.

It took an effort of will to turn her head to look at him.

He kept going more by an effort of will than anything else.

Still, it took some effort of will to pick the thing up.

With an effort of will, he made himself turn green again.