तो सुन भी नहीं

aren’t even listening

→ तो
phrase Rare #11,444
aren’t even listening तो adds emphasis, भी means “even,” and नहीं makes the phrase negative. The ending of the verb changes to agree with the subject.
HI: तुम तो मेरी बात सुन भी नहीं रहे हो।
EN: You aren’t even listening to me.