His health is breaking _

🧠 Explanation:

In the phrase "His health is breaking _," the correct word is "up," forming the idiom "breaking up," meaning deteriorating or declining. Used in contexts like health or relationships, it implies a gradual collapse or disruption. Proper idiom use enhances communication, conveying nuanced meanings effectively. This phrase highlights the importance of choosing the right preposition in idiomatic expressions, a common challenge in English. Understanding such phrases improves fluency, ensuring clear expression in conversations or writing, particularly when describing changes in physical or emotional states.