I've never heard such a ridiculous idea in my entire life.
All the same, if she hadn't known it to be a ridiculous idea.
It was a ridiculous idea, something his father could never do.
"Whatever gave you the ridiculous idea that this is the end of the world?"
The other ridiculous idea is that a visiting team cannot bring its school band.
She has the ridiculous idea that her father will show up at any moment.
Buying her a present was a ridiculous idea, out of proportion to the current situation.
But the young men scoffed at such a ridiculous idea.
Imagine, she said, how many people called his idea not merely ridiculous, but impossible.
The home schooling was a ridiculous idea when the age range is so vast.