In traditional grammar books you may have read that the present perfect tense is not used with adverbs referring to definite periods of time. This is quite confusing. Although the present perfect tense is not usually used with adverbs referring to finished periods of time, it is quite common with definite time adverbs.
- I have worked here for three years and two months. (Here the present perfect tense is used with a very definite time-reference.)
- Once upon a time there lived a little girl with her mother. (NOT Once upon a time there has lived a little girl with her mother.) Here the present perfect tense cannot be used because we are referring to a finished period of time.
Note that although the present perfect tense is not usually used with finished time periods, it can be used to refer to finished actions.
- That cat has drunk all the milk. (We can use the present perfect to refer to a finished action.)
- I drank the last ounce of milk this morning. (NOT I have drunk the last ounce of milk this morning – we do not use the present perfect with finished time periods.)
We usually use the present perfect tense to talk about recent events and simple past tense to talk about old events.
- There has been an explosion near the temple.
- Scientists have discovered a new planet that may support life.
Note that there are exceptions to this rule. The present perfect tense is sometimes used to talk about very old events that may have some significance in the present. In the same way, simple past tense can be used to talk about very recent events.
- The Renaissance has influenced every cultural revolution in Europe since the sixteenth century. (Here we are using the present perfect tense to talk about a very old event.)
- Jane phoned five minutes ago. (Here we are using the simple past to refer to a very recent event.)
This is the first time etc
In sentences constructed this / it / that is the first / second / third / only / best / worst etc., we usually use a present perfect tense.
- This is the first time that I have heard this song. (NOT This is the first time that I hear this song.) (NOT This is the first time that I heard this song.)
- This is the sixth time you have asked me the same question.
- It is the best book I have read in a long time.
Note that when we talk about past events, we use past perfect tenses in this structure.
- It was the third cake that I had finished that evening.