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完成体

在描述一个已完成的动作时可以使用动词现在完成态(perfect verb aspect),例如“I have done the dishes".

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hello grammarians today I want to talk to you about the idea of the perfect aspect of verbs and what that means is that it's not you know beyond reproach or that it's like beautiful and shiny now what it means is really that whatever we're talking about whatever action we are talking about is complete so we use the perfect aspect in all tenses to illustrate when something has been completed prior to the present moment so when we talk about the present we're talking about one point now but when we're using when we use aspect it enables us to talk about a period between then and now you're speaking in the now referring to a point previous so we could say using the perfect the way you form the perfect is you simply add have and then you use the past form of the verb so if my assignment for example were to wash some dishes when the dishes were complete I would say to the person that told me to wash the dishes I have washed the dishes so I'm using the present tense form of to have and the past tense form of washed so as with the progressive aspect the thing that changes is the helper verb this part the main verb does not change it remains in the past tense even if we're talking about the present or the future the part that changes is have so if we want to put this story in the past you know talk about a period that is then but also saying that we wash the dishes at a period before then write a time before the moment in the past that we're talking about if that makes sense we would say I had washed the dishes and if we want to talk about something in the future that happens before that future moment but after now we would use the future perfect to say I will have washed the dishes and that's what the perfect aspect allows us to do it allows us to travel backward in time a little bit extra it allows us to say oh well before the point in this story that I'm mentioning this thing was already completed so the it enables us to say here is a thing that happened in the past here is a verb action that has completed in the past prior to the moment I'm talking about so to recap the perfect refers to something finished you can learn anything David out