阅读下面短文,从短文后所给各题的四个选项(A、B、C和D)中选出能填入相应空白处的最佳选项。
Social customs and ways are changing. Things which were considered 【B1】 many years ago are now good. Just few years 【B2】 , it was considered impolite for a man 【B3】 in the street. No man who thought 【B4】 himself as being a gentleman would make a fool of himself smoking 【B5】 a lady was in the room.
Customs 【B6】 change from country. Does a man walk 【B7】 the left or the right of a lady in your country? Or doesn't it 【B8】 ? What 【B9】 table manners? Should you use 【B10】 hands when you eat? Should you leave 【B11】 in your help 【B12】 on the table?
The important thing 【B13】 about social customs is not to do 【B14】 that might make other people 【B15】 uncomfortable, especially if they are your guests. There is 【B16】 old story about a rich nobleman who gave a very formal dinner party. When the food 【B17】 , one of the guests started to eat his peas 【B18】 a knife, The other guests were surprised, but the nobleman calmly picked up his knife and began to eat 【B19】 It would have been bad manners to make the guest feel 【B20】 .
【B1】
A.polite
B.impolite
C.formal
D.informal