Remember that some verbs are not usually used in the continuous form. So instead of the Present Perfect Continuous, they are usually used in the Present Perfect.
I’ve been sitting here in the park for an hour, and I’ve met two friends of mine.
(Not; I’ve been meeting.)
Tom and I have known each other since we were at school.
8. The Present Perfect Continuous is used with for, since and How long…? to say how long something has been happening.
-How long have you been waiting for me?
-I’ve bee waiting for you since 8 o’clock / for two hours.
We use since when we say the beginning of the period (8 o’clock).
We use for when we say the period of time (two hours).
THE PAST PERFECT TENSE
I. The formation of the Past Perfect Tense.
The Past Perfect is formed by means of the Past Indefinite of the auxiliary verb to have and Participle II of the notional verb.
In the interrogative form the auxiliary verb is placed before the subject.
In the negative form the negative particle not is placed after the auxiliary verb.
Affirmative
Interrogative
Negative
I had worked
Had I worked?
I had not worked
You had worked
Had you worked?
You had not worked
He/she/it had worked
Had he/she/it worked?
He/she/it had worked
We had worked
Had we worked?
We had not worked
They had worked
Had they worked?
They had not worked
II. The contracted affirmative forms are:
I’d worked
We’d worked
The contracted negative forms are:
I hadn’t worked
We hadn’t worked
The negative-interrogative forms are:
Had he not worked?
Hadn’t he worked?
Had you not worked?
Hadn’t you worked?
III. The use of the Past Perfect
The Past Perfect expresses an action accomplished before a given past moment and viewed back from that moment.
The porter said that our friend had just left the club.
The storm had died away but very far off the thunder was still muttering.
The past moment from which the accomplished action is viewed may be indicated:
a) By means of an adverbial expression: by four o’clock, by that time, by the end of the week, etc.
By that time the children had already gone to school.
By the end of the week we had already done half of the work.
By six o’clock they had already gathered in the hall.
B) By another action expressed by a verb in the Past Indefinite.
When I came home, everybody had gone to the concert.
I knew that she had left for the South.
◆ Notice that the tense does not change depending on the positive or negative meaning of the context:
We had gone far when we suddenly noticed that dark clouds were beginning to gather.
We had not gone far when we suddenly noticed that dark clouds were beginning to
gather.
◆ The definite moment need not necessarily be expressed in the same sentence as the action expressed by the Past Perfect.
Everybody noticed how sad she was the whole evening. She had got an unpleasant
letter.
2. The Past Perfect is used with the conjunctions hardly…when,
merely…when,
barely…when,
scarcely…when,
no sooner…than.
He had hardly entered the room when he heard some noise.
For the sake of emphasis the word order is often inverted.
No sooner had the bell gone than the teacher entered the classroom.
3. The Past Perfect is frequently used with the adverbs just,
Already,
yet.
Elsie, who had not yet assumed the white cap, was sweeping the stairs.