Практическая грамматика

§ 8. The Past Indefinite and the Present Perfect.
An action expressed by the Past Indefinite belongs exclusively to the sphere of the past, while the Present Perfect shows that a past occurrence is connected with the present time.
She is not well and has changed very much of late.
She changed very much a great many years ago. (Dickens)
The Present Perfect is never used with such adverbial modifiers of the past time as yesterday, the other day, last week, etc. With such adverbial modifiers as today, this week, etc. both the Present Perfect and the Past Indefinite are used. The tenses are used according to the principle mentioned above.
I have told you three times this week that she is coming home for a year. (Dreiser)
I want your sister, the woman who gave me money today. (Dickens)
With the adverb just the Present Perfect is used.
I have just hired a new pianist from St. Joe—a Negro. (Dreiser)
With the expression just now the Past Indefinite is used.
I saw you come in just now. (Dreiser)
Just now is less frequent than just.


The Past Perfect


§ 9. The use of the Past Perfect.
1. The Past Perfect denotes an action completed before a certain moment in the past. The moment may be indicated by another past action expressed by a verb in the Past Indefinite or by an adverbial phrase.
After she had cried out, she felt easier. (Heym)
Fortunately the rain had stopped before we started. (Bennett)
By this time he had written Aileen under no circumstances to try to see him. (Dreiser)
The definite moment can be understood from the situation.
The Squire had laid down his knife and fork, and was staring at his son in amazement. (Eliot)
The Past Perfect is used with the conjunctions hardly... when, scarcely... when, no sooner... than.
Mrs. Winthrop had no sooner left the room than they began to gossip about her. (Austen)