Grammar of politeness

Using tag questions : They bought a new PC yesterday , havent they?

Explanation of politeness

Indirect speech: She said this laptop isn't for gaming

Euphemism : You have hard bones. ( instead saying " you are fat" )

Negative politeness

"Would you mind if I ask you a question?"

Definition: Using polite expressions (non-offending) in respect to person's right to act freely

Polite lie: varies between cultures - for example when you say "no" to Japanese they can see that as impolite
Japanese PC dealer : Do you want to see this product?
English customer : "No" , I dont want to.
Japanese PC dealer : You are so rude.

Positive politeness

"I hope you don't think me rude, but your tie is hideous"

Definition: Using impolite speech in communication with friends

Examples of polite questions :
Could you please pass me over this CD?
Would you like to help me around this homework?