How do we use it? Examples.

For irregular verbs, use the participle form (see list of irregular verbs, 3rd column). For regular verbs, just add “ed”.

Use of Present Perfect

• puts emphasis on the result:
  Example: She has written five letters.
  
  
• action that is still going on:
  Example: School has not started yet.
  
  
• action that stopped recently:
  Example: She has cooked dinner.
  
  
• finished action that has an influence on the present:
  Example: I have lost my key.
  
  
• action that has taken place once, never or several times before the moment of speaking:
  Example: I have never been to Australia.