present perfect

常見例句

When you ask about something that started in the past but continues to the present time, you use the Present Perfect tense, e.g.
當(dāng)你談?wù)搹倪^去開始一直持續(xù)到現(xiàn)在的某件事時(shí)，用現(xiàn)在完成法時(shí)態(tài)。
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When you ask about something that started in the past but continues to the present time, you use the Present Perfect tense, e.g.: I’ve been there for 5 years / I’ve been there for 5 years.
當(dāng)你談?wù)撛谶^去開始但是一直持續(xù)到現(xiàn)在的某事時(shí)，用現(xiàn)在完成時(shí)態(tài)，例如：I’ve been there for 5 years/我在那里已經(jīng)5年了。
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If we say when a past event happened (for example, by using time-adverbs), we do not usually use the present perfect.
說過去發(fā)生的事件（例如：用過去時(shí)間狀語），我們通常不用現(xiàn)在完成時(shí)。
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