I am asking because for example the answer they give for the 2nd one is next: He is said to be an excellent pianist.( and it’s really wired)

Have these letters been opened? He is said to be an excellent pianist. What will he be asked? I purposely omitted the subjects ("anyone", "they"). You can certainly keep them, but I feel that the only real advantage of passive voice is that it allows the actor to be omitted.

Thanks for your help ♥️

Have these letters been opened by anyone? He is an excellent pianist has been said by them. (This would be a weird way of saying it. Better would be - It is said that he is an excellent pianist) What is it that he is going to be asked? This is weird too.

Have these letters been opened by anyone? It is said that he's an excellent pianist. What is he going to be asked by them?