Answer:
The soldiers are "at" war.
In this sentence, the appropriate preposition to use is "at." When we talk about being involved in or participating in a conflict or battle, we use the preposition "at." It shows that the soldiers are actively engaged in the war.
Here's an example to illustrate the use of "at" in this context: "The soldiers are at war with the enemy forces."
Using the preposition "in" would not convey the same meaning in this sentence. While "in" can be used to describe being inside a physical location, when discussing war or conflict, we use "at" to express direct involvement or engagement.
Therefore, the correct preposition to fill in the blank is "at."
Step-by-step explanation:
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