English Grammar - Verbs - Present Perfect

FORM Present Perfect

[HAS / HAVE] + [past participle]

Examples:
We have never talked to each other.


USE 1 Unspecified Time Before Now


The most important thing to remember about the present perfect is that it can never be used with adverbs which describe finished time periods, such as yesterday, five minutes ago and at three o'clock. If a time adverb is used with the present perfect, it should describe a time period which is unfinished. Example include today and this week.

We use the Present Perfect to say that an action happened at an unspecified time before now. The exact time is not important. You CANNOT use the Present Perfect with time expressions such as "yesterday," "one year ago," "last week," "when I was a child," "when I lived in Japan," "at that moment," "that day" or "one day." We CAN use the Present Perfect with expressions like "ever," "never," "once," "many times," "several times," "before," "so far," "already" and "yet."

Examples:

I've lived in Austin for eight years.
There have been many tsunamis in Indonesia.
People have traveled to the moon.


We can distinguish three situations where the present perfect is used, although there is a lot of overlap between these situations.

They can be described as:

To describe 'experiences'
To describe the duration of continuing states and actions
To describe a past action with a result in the present


TOPIC 1 Experience
You can use the Present Perfect to describe your experience. You can also use this tense to say that you have never had a certain experience. The Present Perfect is NOT used to describe a specific event.

Examples:

we have been to USA.
We have been to USA three times.
We have never been to USA.
Philips has studied Spanish


TOPIC 2 Duration of continuing states and actions
We use the present perfect simple to describe the duration ('How long...') of a state which is true now.
Examples:

I have been in the US for six months.

We have been watching TV since four o'clock


TOPIC 3 Accomplishments - past action with a result in the present

We often use the Present Perfect to list the accomplishments of individuals and humanity. You cannot mention a specific time.

Examples:
My son has learned how to write.
Policemen have stopped a lot of criminals
She's broken her glasses.


Just
'Just' is commonly used with the present perfect simple to show that an action happened very recently. When 'just' is used the result referred to is often indirect, and this form can be used if you want to make it clear that the action is complete while at the same time explaining an indirect result of the action:

I've just washed the car, which is why I'm wet.