The phrase "breaks out" is commonly used to refer to sudden and unexpected situations, such as a conflict, a disease, or an outbreak. Some synonyms that can be used to replace "breaks out" in such contexts include erupt, flare up, spark, ignite, burst, commence, start, and begin. Each of these words carries a slightly different connotation and context, so it's important to choose the right synonym based on the situation you are referring to. For instance, "erupt" suggests a sudden and violent outburst, while "spark" implies a less intense beginning. Choosing the right synonym can add more depth and precision to your writing.