Unit 8. Present perfect (2) (I have done)

  When we talk about a period of time that continues from the past until now, we use the present perfect (have been / have travelled etc.) 

• Have you ever eaten caviar? (in your life)
• We've never had a car.
• Have you read Hamlet? / No, I haven't read any of Shakespeare's plays.

In the following examples too the speakers are talking about a period that continues until now (recently / in the last few days / so far / since breakfast etc.)

• Have you heard from George recently?
• I've met a lot of people in the last few days.
• Everything is going well. We haven't had any problems so far.

We use the present perfect with today / this morning / this evening etc. when there periods are not finished at the time of speaking

• I've drunk four cups of coffee today. (perhaps I'll drink more before today is finished)
• Have you had a holiday this year (yet)?

Note that we say 'It's the first time something has happened' (present perfect). For example : 

Don is having a drving lensson. He is very nervous and unsure because it is his first lesson.

• It's the first time he has driven a car. (not 'drives')
• He has never driven a car before.