Possible Clues:

• A European has it in him to be courteous
• Like thank-yous
• Not to cause offence, have it in the one from Poland
• It sounds 9 across for it to be in a polar setting
• Cut it up and tie it in a knot? That's a nice way to behave!
• Is it in one from Poland to be so diplomatic?
• Cut it back and tie it in a knot to have it polished
• Civil and good-mannered
• Courteous staff accept it
• Courteous European retaining appeal