cut the ground from under sb's feet

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If you cut the ground from under someone or cut the ground from under their feet, you make their ideas or opinions seem less impressive, often by doing something unexpected.

如果你cut the ground from under someone或cut the ground from their feet，通常是通过做一些意想不到的事情来使他们的想法或观点看起来不那么令人印象深刻。

I plan to cut the ground from underneath the prosecutor's feet with this line of questioning.

我打算用这一连串的问话来拆检察官的台。