present perfect

                                                      present perfect

USE
* show action which began in the past but which continous into the present.
ex.Betty has taught for ten years.
(she started teaching 10 yearsago,and she still teach now.)

*show action which happened in the past but is important at the time of speaking.
ex. I can not get in my  house,I have lost my keys.
(I lost my keys in the past.but it's important in the present.)

*an action performed during a period that has not finished.
ex.she has been to the cinema twice this week.
(the week is not over yet.)

*A repeated action in an unspecified period between the past and now.
ex. We have visited Stockholm sevsral times.

*an action that was completed in the very recent past" expressed by just.
ex. I have just finished my wok.


they say so present perfect has multiple ways of use good example , an action when time is not important.