不是
两者区别（判读依据）在于：逻辑主语是否与主语一致
若非谓语动词的动作执行者（逻辑主语）与主语一致,则是分词的独立结构,形式“分词+.”
例句：as we were late,we had to do it.= being late,we had to...
若非谓语动词的动作执行者（逻辑主语）与主语不一致,则是独立主格结构,形式“逻辑主语+分词、形容词、副词”
例句as mom was ill,i had to go home.= mother being ill,i had to...=mother ill.i had to...
清楚了吗?我也是才搞懂的.