소년이

소년이

"소년이" means "boy" (subject particle attached).

Here, '소년이' is the subject of the sentence, indicating who is performing the action of playing.

소년이 공을 가지고 놀고 있다.

The boy is playing with the ball.

In this sentence, '소년이' is again acting as the subject, showing who performed the actions of writing and sending.

소년이 부모님에게 편지를 써서 보냈다.

The boy wrote and sent a letter to his parents.

Here, '소년이' introduces the person whose spoken words are being referenced in the imperative sentence.

소년이 한 말을 기억하세요.

Remember what the boy said.