Breakdown of Он перестал курить год назад.
он
he / it (for a masculine noun) / it (for a neuter noun)
год
year
курить
to smoke
назад
back; ago
Questions & Answers about Он перестал курить год назад.
Why is курить imperfective if he completely finished the action of quitting?
In Russian, phase verbs that show the start, continuation, or end of an action (like перестать) must always be followed by an imperfective infinitive. You can only start or stop an ongoing process, so the action being stopped (курить) must be imperfective, even though the act of quitting (перестал) is perfective.
Could we ever use a perfective infinitive like покурить after this verb?
No, that is a strict grammar rule in Russian. Phase verbs can never take a perfective infinitive. Since a perfective verb focuses on a single completed result rather than a continuous process, it logically cannot be started, continued, or stopped.
Why use перестал here instead of остановился for 'stopped'?
Перестать is used when you stop doing an activity or quit a habit. Остановиться means to physically stop moving, like a person halting their steps while walking or a car stopping at a red light.
What case is год in the phrase год назад?
It is in the accusative case. When using назад (ago) to say how long ago something happened, the time period goes in the accusative. Because год (year) is an inanimate masculine noun, its accusative form looks exactly the same as the dictionary form.