You may have been told to mind and use the Perfect tenses, to look and sound smart. Beware: there are things I would not tell grandpa, not to look and sound pliable. We can compare some rules on the Present Perfect and reckon.

The matter here comes from the BRITISH COUNCIL.

"We use the present perfect tense:
  • for something that started in the past and continues in the present:
She has lived in Liverpool all her life.
Note: We normally use the present perfect continuous for this:
She has been living in Liverpool all her life.
  • when we are talking about our experience up to the present:
Note: We often use the adverb ever to talk about experience up to the present:
My last birthday was the worst day I have ever had."


You see, I could tell grandpa we have been living together for some 40 years, but he would  be likely to ask if I want to move. Worse still, if I said he was the most handsome man I had ever met, those years ago, he would probably ask if I have a new man.

We people view time mostly in spans and extents. The Perfect tenses mark time spans. We do not have to mean something ends, when we use a Perfect tense, but quite often it is so: if we say we have done our housework or homework, we are finished with it.

It is a bit as with earthly gravitation, in human grammar. Basically, we live on Earth. We can express it with the Simple Aspect. Other Aspects always add or emphasize.
We live at the Sunrise Avenue.

If we are living somewhere, we highlight it is not our regular place of residence, we are somewhere temporarily, or there is something irregular or temporary in the manner of our stay that we want to talk about.

At the Sunrise Avenue, we are living high expectations now: Jim has passed his university exams.

If we say we have lived somewhere, we focus on the time span.
We have lived some 40 years at the Sunrise Avenue, and we have never seen it trashed.

With the Perfect Progressive, we join the highlight on span with that on irregularity or intensity (our values TO and IN).
We have been living together for some 40 years, and you have never told me you prefer your coffee and cream separate. (In other words, I can't believe we have been together ALL THIS TIME, and you have never told me that.)

For the gravitation effect, we can use the Perfect when we do not have a specific ground. Let us think about grandpa and his automobile magazine. He happens to look for it.

I have seen it somewhere by the garage door.
 (I am not sure specifically where, or specifically when.)

I saw it by the garage door, in the morning.

Well, and grandpa remains the most handsome man I have ever met. You will maybe know one day, this way people see each other, having had a good life together.

Travel in Grammar has more on the Perfect Aspect.