精选优质文档-倾情为你奉上暑期学习一:现在完成时讲解(2)用法:1)现在完成时通常表示在已经完成的动作或持续一段的时间状态状态。说话人强调的是该动作或状态对现在的结果或影响。(1)构成:现在完成时由助动词have + 过去分词构成。第三人称单数用has,其余用have.现在完成时的否定式直接在助动词后面加上not、疑问式是把助动词提到主语之前否定式疑问式I have not (havent) studied.Have I studied?You have not (havent) studied.Have you studied?He has not (hasnt) studied.Has he studied?否定疑问式简单回答(肯定/否定)Have I not (Havent I) studied?Yes, you have. No, you havent.Have you not (Havent you) studied?Yes, I have. No, I