单项选择题 What way to eat bread is proper？（）

单项选择题 Use for a napkin only for your（）.

单项选择题 When should the buyers open a letter of credit in a transaction？（）

单项选择题 A gentleman must help a lady whom has escorted to the table，to all she wishes；but it is improper for him to offer to help other ladies who have escorted.The word "escort"means ？（）

单项选择题 What is the "continental"style of dinning？（）