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The difference between present perfect and past simple
Is the time Sheila joined the Sierra Club the same or different?
* Sheila has joined the Sierra Club.
* Sheila joined the Sierra Club.The use of the present perfect has more to do with our present perspective on the event rather than on the actual time at which it took place.
Present Perfect or Simple Past?
* The simple pasttense occurs with specific past-time adverbials. The core meaning of the past tense is remoteness. The use of specific past-time adverbials (e.g., yesterday, last year, 1990) makes the past tenseobligatory. The use of certain more general temporal adverbials is commonly associated with the perfect (e.g., already, since, yet).
* Organise the phrases in the next slide into three columns headedused with simple past, used with present perfect and used with either.
In the last century | Up to now | During Kennedy’s lifetime |
For three months | Over the last hundred years or so | Threemonths ago |
Recently | Since three months ago | This is the first time I |
Throughout the 17th century | Lately | Since the Vietnam War |
Within the last three months | Today | Afterthe Second World War |

* Even if a past-time adverbial isn’t explicit, the remoteness may be defined elsewhere in the context or simply implied:
* John Lennon was a creative genius.* The past tense is used for a completed historical period versus an incomplete one:
* My father lived here all his life.
* My father has lived here all his life.
* The function ofthe present perfect is to change the nature of the relationship between the subject and predicate – it emphasizes the predicated event’s result.
* I’ve been to Japan twice already, but I stilldon’t speak much Japanese.
Overview
* Past simple is used by speakers to talk about past events which are, or which they regard as, finalized, or over and done with.
* Present perfect is...