You use Present Perfect tense if an action has started in the past and has a result in the present time
Past Perfect = Subject + has/have + past participle of the verb
*past participle = usually ending -ed, -d, -t, -en, or -n
*example: dreamt, went
- I have washed the car. It is now clean and shiny.
- My sisters have been to Canada for three times. They like it very much.
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