I thought, "Wow, what a good idea."

我想: “哇，多妙的一个主意。”

《柯林斯英汉双解大词典》

What a good idea!

多么好的主意！

《新英汉大辞典》

What a good idea (it is)!

(这是)多么好的主意！

youdao

"She's expected to stay home, not to go away to college or do anything that would betray the family's idea of what it is to be a good daughter."

VOA: standard.2010.07.22

It's a good idea to try and figure out what your goals are-- what you're trying to achieve-- before you go ahead and analyze the game.

它能帮我们在分析博弈之前,先弄清我们的目的是什么

耶鲁公开课 - 博弈论课程节选

So that you get a good idea of what people do in their free time and what the dorms are like.

所以你可以了解人们闲暇时间做什么，宿舍什么样。

沟通很重要 - SpeakingMax英语口语达人

This is, of course, self-serving stuff, intended to show that New Labour folk, unlike the Tories, are careful stewards of the economy and in particular, what a good idea it was to give the Bank of England control over interest rates.

ECONOMIST: Singing in the rain

Details are what matter, and are what make a good idea stand out.

FORBES: 10 Ways To Clean Up Your Creative Process

Another reason the auction may not attract many participants is that what seemed a good idea just a few years ago has been overtaken by business and technological developments.

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