We use this expression to try to calm someone down.
You can use this phrase in ………… language.
Spoken
Informal
Example 1
A: If he says we should work harder one more time I’ll hit him!
B: Now, now. Just calm down. We can’t change him.
Example 2
A: I refuse to work with him. He’s such an idiot!
B: Now, now. That’s not very nice of you.