1)
What is "Shav Yedaberu"?
1.
Radak: They speak with their mouths what is not in their hearts.
2.
Malbim: They lie about Emunos and mindsets.
2)
What is "[Sefas] Chalakos"?
1.
Radak #1: It is a noun (flattery).
2.
Radak #2: It is an adjective. The noun it describes is omitted, i.e. Imros Chalakos (flattering words).
3.
Malbim #1: It is a flattering expression to conceal the Sheker.
4.
Malbim #2: It is [Sheker] between people; refer to 12:3:1:2.
3)
What is "b'Lev va'Lev"?
1.
Rashi: It is with two hearts - they show to me Shalom, and there is hatred hidden in their hearts.
2.
Radak: With their words they show a good heart [to help], and [really,] there is evil in their hearts.