What is the Plural form of sentence army fought bravely?

The plural form of "sentence army fought bravely" would depend on what you want to pluralize.

Here are a few possibilities:

* Pluralizing "sentence": If you want to talk about multiple sentences, you'd say "Sentences in the army fought bravely."

* Pluralizing "army": If you want to talk about multiple armies, you'd say "Armies fought bravely."

* Pluralizing "army" and "sentence": If you're referring to multiple sentences within multiple armies, you'd say "Sentences in armies fought bravely."

It's important to consider the context to understand what you want to pluralize.