Answer:
Because there talking in front of there army and don't wont the army to see there leaders arguing.
The distinct way the author uses words.
Answer:
Be able to see beyond? I don't remember the story and I don't even really know if we're talking about the same thing
Voldemort thinks that Snape is the master of the elder wand, so the only way for Voldemort to be the master of the elder wand is to kill Snape. He sends Nagaini to kill Snape because he wants the powerful wand all to himself