Breakdown of Впервые я слышал эту песню в детстве.
песня
song
я
I
этот
this [f: эта, n: это]
слышать
to hear
Questions & Answers about Впервые я слышал эту песню в детстве.
Why is слышал (imperfective) used here instead of услышал (perfective) if this happened for the first time?
Even though it happened for the first time, the speaker is focusing on the general fact of experiencing the song in the past, not on a sudden completion or result. When talking about general past experiences (often called the statement of fact), Russian frequently uses the imperfective aspect.
What is the difference between впервые and в первый раз?
Why does the Russian sentence say в детстве instead of using the word for child?
English often uses phrases like as a child or when I was a child, but Russian naturally expresses this with the prepositional phrase в детстве, which literally means in childhood. You will see this pattern often, for example with в молодости meaning in one's youth.
Could I change the word order and put впервые after я?
Yes, Russian word order is very flexible. Putting впервые at the very beginning of the sentence strongly emphasizes that it was the first time. If you said Я впервые слышал эту песню в детстве, it would be perfectly correct but with a more neutral emphasis.