"A girl sends a letter to a boy."
Translation:여자아이는 남자아이에게 편지를 보냅니다.
Interesting, since the app normally doesn't accept answers written in 반말.
Although, it's of minor note that 소년 really means juvenile (Literally, it's "young years"), even if it often is used to mean a boy. For instance, a "juvenile detention center" is "소년원" and it's not a place for just boys.
For the 를, the ㄹ is somewhere in between R and L. It's kinda like a combination of both.
If you find it difficult pronouncing 를,
Try saying: "Lil"
but stress the L a bit to make is sound a little bit like R.
If you can't stress the it to make it sound a bit like R, then just say:
Hence, 편지를 is prounounced: Pyeonjilil
...stressing the "l" of course..
I hope this helps...
A basic sentence has three parts: subject (performs the action), verb (the action), and an object (action is performed on). For example, "Bob (subject) punched (verb) James (object)." The difference between 편지 and 편지를 is the use of the object particle 을/를. This particle clarified that the letter (편지) is the object of the sentence. And you can use them inversely but when you start out, you're better off using the particles so that you get more familiar with them. They can be very complicated for a non-native speaker so I recommend using them as often as possible to get more comfortable.