The document discusses the present perfect tense in English. It explains that the present perfect is used to describe actions or situations that began in the past and continue to the present or that occurred multiple times during a period that extends to the present. Specifically, it is used for actions that happened during a period of time continuing to now, actions that began in the past and are still ongoing, and experiences someone has had over a period continuing to now. Examples are provided to illustrate usage with time expressions like "already", "for", and "since".

1. 英語時態 – 現在完成式Present Perfect Theresa Chen iumschen@nkfust.edu.tw http://blog.yam.com/btowncat

2. Ihad a little pink piggy. Finally, the pig will be pork. 過去式 現在式 未來式 過去完成式 現在完成式 I am walking with my pig. has/have +p.p had +p.p

3. When to use Present Perfect? Things or actions that happened during a period of time that continues up to the present. 持續一段時間的動作並且持續到現在 It is often used with adverbs of time like: already (已經), just(僅僅), so far(到目前為止) EX: They have already finished that assignment. EX: So far, Tom has climbed Mount Everest twice. 過去某時間點 現在時間點

4. When to use Present Perfect? An action or situation that begins in the past and continues. 描述一個發生在過去的時間點的事件並且持續進行中 Often used with: for(已經) +一段時間, since(自從)+某過去時間點 友誼仍然會持續下去 I have known Jessica for a long time. Kevin has lived in the United States since 1978. 仍然會繼續居住在美國

5. When to use Present Perfect? Talk about experiences someone has had during a period of time that continues up to the present. 表達已經持續一段時間的個人經驗並且會持續進行 It is often used with adverbs of time like: Ever(曾經), never(不曾), again and again(一次又一次), several times(好幾次) My boss has gone to Europe and will not be back till June 6. My boss has been to Europe many times.

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