A       : “Hy… you look sad. Why?”
B       : “I have a trouble with my tooth” 
A       : “I am sorry to hear that. How it is now?”
B       :  “It is not better”
A       : “How if you go to doctor”
B       : “Yes, you are right. I must go to doctor. Thanks for suggestion”
A       : "You are welcome”
A: your eyes look puffy, what's wrong?
B: my cat died yesterday
A: oh... i'm sorry to hear that