He surely went off the deep end when he bought that restaurant.

他买下那家饭店的确太贸然行事了。

《新英汉大辞典》

You better think it over and don't go off the deep end.

你最好要深加考虑，不要立即下结论。

youdao

Hearing this sarcastic remark, he went off the deep end.

一听到挖苦的话，他就勃然大怒。

youdao

"As with so much, the Bush administration has gone off the deep end, " Clinton said.

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Let's face it, some high-income taxpayers went a little crazy in recent years, and some tax advisers went clear off the deep end.

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Yet when you have Donald Trump defending your new policies, it is as glaring a sign as any that you have gone off the deep end.

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