The Present Perfect Simple Tense

When there is a connection either action and/or result from the past to the present time, we use the Present Perfect Tense.

The present perfect simple is formed with "have/has + past participle".

 It is used for:

1. an action you did in the past but wish not to mention the specific time.

• Have you done your homework yet? ~ Yes, I have. / No, I haven't.
• I have finished the project that you gave me. (Maybe you have forgotten when you finished it or maybe you do not want to tell when you finished it.)
• I have lost my phone. (You do not know the exact time you lost it)

In this case, it is used to talk about:

Experiences:

• I have been to Paris.
• I have never loved anyone.

Changes:

• You have changed a lot since we met last year.
• My English has improved since I moved to this school.
• The bus fee has gone up rapidly.

Accomplishments:

•  They have won a lot of games in the past few years.
• My daughter has learned how to sing.

Uncompleted actions you are supposed to have done (with "yet" in negative sentences):

• I haven't bought the milk yet.
• The teacher hasn't returned us the quiz result yet.

Repeated actions at different time:

• I have been to Paris four times this year.
• We have met a lot of famous people recently.

Used with "yet" to ask if someone has completed a task:

• Have you done the washing yet? ~ Yes, I have. / No, I haven't.
• Has he watched that movie yet? ~ Yes, she has. / No, she hasn't.
• Has the teacher check the attendance yet? ~ Yes, he has. / No, he hasn't.

An action which was completed earlier than expected. (with "already" in positive sentences):

• Can you go to the market and get some oil? ~ I have already bought some.
• Don't forget to water the flowers. ~ No worry. I have already asked Jane to do it.

2. We also use the present perfect simple tense to talk about continuation in the present (an action that happened in the past and continues until now with "for" (a period of time until now" and "since (from a specific time in the past until now")

• I have learned English for 3 years.
• She has worked as a waitress for 6 weeks and now she's tired of it.
• They have stayed in that village since October.