Still, like two children, they find the challenge irresistible.

"I suspected that at some point Lisa would find a new challenge irresistible," he said.

He became an irresistible challenge, but no one could win him.

Still, for a young democratic nation, dedicated to reforming society and its institutions, the prison was an irresistible challenge.

Built by the Revolutionary government, this magnificent mountain highway is an irresistible challenge for cyclists.

Or designers at fashion's cutting edge may see an irresistible challenge in plucking the flower and making it modern.

Richard finds this kind of cooking an irresistible challenge.

But for many that is just one more irresistible challenge.

But for the Queen Favor, the woman posed an irresistible challenge.

But Cook has chosen well, gathering men to whom the move is an irresistible challenge.