The Chinese idiom 心烦意乱 (xīn fán yì luàn) is formed through a parallel and symmetrical four-character structure, where "心烦" (heart troubled) and "意乱" (mind chaotic) are combined. Each two-character segment describes a related aspect of inner turmoil: "心" (heart) and "意" (mind) are synonymous nouns referring to one's mental and emotional state, while "烦" (annoyed/agitated) and "乱" (disordered/confused) are synonymous adjectives intensifying the description. Together, they create a compound that vividly emphasizes a state of being emotionally upset and mentally distracted, with the repetition reinforcing the overall sense of overwhelming distress.