Questions & Answers about Я начну изучать грамматику.
Why is the verb начну used here instead of начинаю or буду начинать?
Начну is the first-person singular future form of the perfective verb начать. Perfective verbs in Russian don’t have a present tense—they only express completed actions. So начну means “I will start” as a single whole event. In contrast, начинаю is the present tense of the imperfective начинать (“I am starting” or “I start” right now), and буду начинать would be a periphrastic future of the imperfective (“I will be starting”), which emphasizes the process rather than the moment of beginning.
What is the difference between начать and начинать?
Начать is the perfective infinitive (to begin/do something to completion), and начинать is the imperfective infinitive (to be in the process of beginning or to habitually begin).
• Imperfective (начинать): describes ongoing, repeated, or habitual actions (“I’m starting,” “I used to start”).
• Perfective (начать): describes a single, complete action (“I will start,” “I started once”).
Why is изучать in the imperfective aspect and not the perfective изучить?
Изучать (imperfective) focuses on the ongoing process of studying. When you say Я начну изучать грамматику, you indicate you’re beginning the process, not necessarily finishing it. If you used the perfective Я начну изучить грамматику, it would sound odd, because you’d be saying “I will start to learn completely,” but the perfective изучить already implies completion (“I will learn/learned”). Generally, perfective + perfective infinitive is unusual when you mean “start doing something,” so you pair perfective with imperfective .