Теория:

Study some information about positive sentences in Past Perfect.
 
Для образования утвердительного предложения в Past Perfect необходимо использовать вспомогательный глагол had и основной глагол в третьей форме (если это неправильный глагол), либо глагол с окончанием -ed (если глагол правильный).
Subject \(+\) had \(+\) V\(3\)/Ved \(+\) other parts of the sentence.
 
              I                  
                                                               had studied
 
       
            you
 
had studied
 
he, she, it
 
had studied
 
we
 
had studied
 
You
 
had studied
 
They
 
had studied
 
 
Examples:
 
Jack had already gone to bed when his parents came home.
  
sleeping-1311784_640.png
Рис. \(1\). Boy sleeping
 
I had cooked pasta and meat by \(6\) o'clock yesterday.
  
spaghetti-1987454_640.png 
Рис. \(2\). Pasta
  
Источники:
Рис. 1. Boy sleeping, 2015, https://pixabay.com/images/id-1311784/ Pixabay License CC0 Free for commercial use No attribution required
Рис. 2. Pasta, 2017, https://pixabay.com/images/id-1987454/ Pixabay License CC0 Free for commercial use No attribution required