讲解细致、全面,适合新授课
现在分词一般式 (doing) : 表示与谓语动作同时 发生,或发生在谓语动作之后. 现在分词完成式 (having done ): 表示动作发生在 谓语动作之前,强调时间的先后关系.
(3)
He went out , shutting the door behind him. Walking around the city, we were impressed by it’s new look. Having finished the letter, he went to post it.