The present perfect simple
(for a past action with a present result)
We use the present perfect simple when we talk about the present result of a past action.
– People have polluted the sea.
– They have not taken care of animals.
Form
– have/has + past participle (3rd form below).
Regular verbs
– polute polluted polluted
– plant planted planted
– destroy destroyed destroyed.
Irregular verbs
– be was/were been
– cut cut cut
– take took taken.
Present perfect + already/yet
(to talk about time up to the present)
A. + yet (to ask if an action has been done)
– Have you met her, yet?
B. + yet (to show that an action hasn’t been done up to now)
– No, I haven’t met her, yet.
C. + already (to show that an action happened sooner than expected)
– Yes, I have already met her.