Wading through the stream, a rock cut one of my bare feet.
【正确答案】：When I was wading through the stream, a rock cut one of my bare feet.
【题目解析】：a rock和wade之间不存在主动或被动的关系，所以不能用独立主格结构做状语。wade意为”涉水“，其动作是由人所发出的，根据后面的my可知主语应为I，when意为”当......时“。句意：当我涉水过河时，一块石头划破了我的一只脚。