PRESENT PERFECT SIMPLE
(1) An action in the indefinite past.
(2) An action in the recent past connected to the present.
(1) I have tried many times to learn French but my friend has succeeded in speaking it properly.
(2) I have worked really hard this morning and I have decided to take a break. In fact I have just started to take my lunch.
All the sentences are positive. In order to make them negative, we have to change them as:
(1) have not (haven't) tried / has not (hasn't) succeeded.
(2) have not (haven't) worked / have not (haven't decided/ have not (haven't started.
All the sentences are statements. In order to make them interrogative, we have to change them as:
(1) Have I tried? / Has my friend succeeded?
(2) Have I worked? / Have I decided? / Have I just started?
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