激烈爭吵 (尤指經常發生者)。
例句：
- We get on very well as adults but as kids we fought like cat and dog. (我們長大後相處非常融洽，但小時候我們經常爭吵不休)
- Frank and his wife still love each other very much. But they fight like cat and dog. (法蘭克和他太太彼此仍很相愛，但他們經常大吵大鬧)
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