现在分词完成式所表的动作发生在谓语动词所表的动作之前，常用作状语，表时间和原因。表时间常置于句首，表原因时常置于句末或句首。如：
Having noted down our names and addresses, the policeman dismissed us. 那警察把我们的姓名和地址记下之后就让我们走了。(表时间)
I was unable to accept your invitation, having promised to accompany my mother to the concert. 我因已答应陪我母亲赴音乐会而不能接受你的邀请。(表原因)
Not having met him, I cannot tell you what he is like. 我没有见过他，所以说不出他的模样。(表原因)
现在分词完成式一般不用作定语。
现在分词完成式亦可用于分词独立结构。如：
My turn having come round, I was ushered into the examining room. 轮到我时，我就被引入考试室。
现在分词完成式有时可被现在分词一般式所代替。如：
Passing through the wall of mud, they found a cheerful company assembled. 穿过土墙，他们发现有一伙人欢聚在一起。(passing=having passed)
有时表已完成的动作，但二者的含义稍有不同;前者与谓语动词无时隔，后者与谓语动词则有时隔。试比较：
Locking the door, she went out. 她锁上门走了出去。(locking与went out无时隔)
Having finished his pipe, he rose from the table. 他抽完了烟斗之后，从饭桌站了起来。(having finished与rose有时隔，以免唐突无礼)
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