I just found out today that when you say:
You are so good at it.
It could mean sexual intercourse?
"It" can refer to playing the trombone or decorating a cake as well.
Or creating PowerPoint presentations.
Or drawing anime.
It could mean an almost infinite variety of things. As with almost everything, you need CONTEXT to be sensible.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.