How do I use verbal aspect in the past tense?

In Russian, verbal aspects are used to indicate the state of the action that you are talking about. In English we can distinguish between ongoing actions (e.g. “I have been reading a book”) and completed actions (“I read a book”/“I have read a book”) by adding ‘have’/‘had’/‘have been’. However, Russian instead uses aspects to make this distinction: Imperfective (past) – used for an action that was ongoing/regular/simultaneous with other actions in the past. The focus is on the process of the action rather than the result.Perfective (past) – used for an action that was completed in the past. The focus is on the result of the action, so the completion of the action is crucial to the meaning of the expression. Here’s a comparison of how the aspects can be used: Читать/прочитать (impf./pf.) – ‘to read’:·     “Я читала книгу весь день.” (‘I was reading a book all day.”): the process of reading the book was ongoing for a whole day. Whether or not the book was completed is not important here.·     “Я прочитал книгу от начала до конца.” (“I read the book from start to finish”): the result of the action – finishing the whole book – is the focus here.