Answer:
thanks for the points ☺️☺️☺️
I know a lot of other languages (including Korean) but I have never heard of that. I asked my language teacher, and even she didn't know, so I don't know if that is even something.
Answer:
When talking to a friend - eres
When talking about yourself - soy
1 - eres
2 - soy
3 - eres
4 - eres
5 - soy
6 - soy
Pretty sure it would be 4. Inversion, 1. Root, 2. Root position, 3. Common tone