Final answer:
The phrase 'fought like cats and dogs' is inappropriate language for formal writing.
Step-by-step explanation:
The part of the sentence 'fought like cats and dogs' is inappropriate language for formal writing.
In formal writing, it is important to use precise and professional language. The phrase 'fought like cats and dogs' is an informal expression and does not convey the intended meaning in a formal context. Instead, a more appropriate phrase could be used to describe the conflict between the opposing factions.
Learn more about Formal Writing