Rashi on Isaiah
What to you mean Heb. מַלָּכֶם, like מַה לָכֶם, what do you mean? [lit. What is to you?]
Ibn Ezra on Isaiah
מלכם What mean you ? Dagesh in ל compensates for the omitted מה לכם ═ מלכם .ה is compounded, of two words, like (מה זה ═)מזה What is that (Exod. 4:3).
Rashi on Isaiah
you grind Crush and degrade to disgrace them in their lawsuit.