What's going on in the cave? I'm curious. "I have no idea."
That's my idea.
He's given to going overboard every time he gets a new idea.
Math is like love - a simple idea, but it can get complicated.
His idea doesn't make any sense at all.
For people who dislike the idea of giving money, a gift certificate is a good idea.
I had been thinking about our new project for two weeks, but I couldn't come up with a good idea.
The development of a new business idea is no doubt the ideal that everybody wishes for.
Taking all things into consideration, I have made up my mind to give up the idea.
Never work on electrical wiring without unplugging it; it's a bad idea. I know from experience.
Our opinion is an idea which we have; our conviction an idea which has us.
Having a few extra batteries handy is never a bad idea.
Is there any difference between your idea and hers?
He's a really straight-laced guy, so he doesn't like the idea of his son changing jobs.
We'd better brainstorm about it together and get a better idea.