One day, I attended a book fair.
"Are you interested in the encyclopedia?" A salesman asked.

"Yes, I am interested in that, but I am not interested in buying that"
I responded.
The discussion of salesmans in Anti-Ramp of BBS recall my memory. Those user or my younger classmates focused the body language how to reveal the rejection but looks so complicated. Maybe we won't easilly distinguish the others' thought and cause them just wasted time.