Today we have had a very open-minded, frank, and straightforward manner discussed what can be done and what cannot be done.

WHITEHOUSE: Signing of New START Nuclear Arms Treaty with Russia

When this type of environment becomes the norm, the human mind that wants to be urgent, becomes urgent about the rules of what CANNOT be done.

FORBES: 5 Tips for Getting Complacent Employees Urgent

Mr Fazio's power over what can or cannot be done in Italian banking is legendary.

ECONOMIST: Italy's way with bank reform

But Thursday's summit will have to work out what - more than just words - can and cannot be done.

BBC: Greece on a knife-edge ahead of euro-crisis meeting

What happened in the past cannot be undone, but that doesn't mean we have to continue doing what was done then in ignorance.

NPR: Soccer Fields Latest Threat to Thoreau's Woods

"Ultimately, what this spill shows is that offshore oil drilling simply cannot be done safely, " Sen.

WSJ: Oil Industry Recommends Offshore Safety Measures After Gulf Spill