Communication skill

"Can you give me tips & trick , on how to know when the customer is ready to close the deal?" , a question in one of my session.

Suppose we should come home very..very ... late after midnight ...and find our wife angry with us ! Sometimes we ask her "Are you angry ?" - and what usually is the answer ?

Most participants in that session answered, " She'll say ...No, I'm not angry!" - I was assuming the same one as well ! The point is, we know she was angry even when she said "I'm not angry !".

Human have incredible ability to understand others ! We did it naturally - specially with those who are closed with our heart.

I tried my answer as "If you know your wife was angry, then you should be able to read costumer !"