Verb Aspect

imperfective (process) and perfective (completed).

делать / сделать

delat' / sdelat'

to do (process / completed)

📝 imperfective / perfective pair

писать / написать

pisat' / napisat'

to write

📝 Often a prefix marks the perfective

The core distinction.

Я читал книгу.

Ya chital knigu.

I was reading a book.

📝 Imperfective past = process

Я прочитал книгу.

Ya prochital knigu.

I read (finished) the book.

📝 Perfective past = completed

Their 'present' form is future in meaning.

Я пишу письмо.

Ya pishu pis'mo.

I am writing a letter.

📝 Imperfective present (ongoing)

Я напишу письмо.

Ya napishu pis'mo.

I will write a letter.

📝 Perfective present-form = future