The present perfect simple, Present perfect + already/yet

1. 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.

– have/has + past participle (3rd form below).

– polute, polluted, polluted;

– plant, planted, planted;

– destroy, destroyed, destroyed.

– be, was/were, been;

– cut, cut, cut;

– take, took, taken.

(to talk about time up to the present)

(to ask if an action has been done)

– Have you met her, yet?

(to show that an action hasn’t been done up to now)

– No, I haven’t met her, yet.

(to show that an action happened sooner than expected)

– Yes, I have already met her.