Which sentence correctly uses 'shoulder' as a verb? A. She rubbed her sore shoulder B. The road has narrow shoulders C. He shouldered the responsibility D. They stood shoulder to shoulder 答案解析 核心考点：词性转换识别 解题思路：动词'shoulder'意为'承担'。C选项正确展示动词用法，其他选项均为名词用法（A身体部位，B道路边缘，D固定搭配）。易错点在于忽视词性变化对词义的影响。 正确答案：C