shudder at the thought of=shudder to think of)
They cannot happen, because if they did, I shudder to think of the consequences.
LEO MELAMED (Chicago Mercantile Exchange) : I shudder to think if all of that stopped.
I still shudder to think what would have happened if I'd been shot down and survived.
I shudder to think how big the bill will be.
I shudder to think what she might propose next.