What the present perfect can do

Form: has or have + past participle: has found, have eaten, have lived.

What it can do:

• a past event with a present result: 'She has found her book' (she has it now);
• something just completed: 'I have just eaten a mango';
• life experience: 'Have you ever seen a play?';
• an accomplishment: 'I have finished my project';
• change over time: 'Meera has grown into a fine singer over three years';
• repeated actions: 'We have visited that fort several times';
• duration up to now: 'My uncle has worked at the post office for ten years' (and still does).

Has or have? has with he, she, it and singular nouns; have with I, you, we, they and plurals.