who occupied the back banches in the classroom on the day of the last lesson? why?

The villagers occupied the last benches of the classroom in order to pay homage to the French teacher M. Hamel for his 40 years of service and to also display their regret of not showing the will to learn French, their native language, when they had the opportunity to do so.

the villagers had occupied the last benches of the classroom on that day...as it was the last class of french and M. Hamel would go the next day. the villagers also wanted to show their regret of not showing the will to learn french-their native language, when they had the opportunity to do so.
 

the old people of the village occupied the last benches to give a farewell to Mr. M.Hamel. He was one of the most reputed teachers tof the village. And he would be no longer teaching as french was banned there. So, to give a final goodbye to him, Everyone was present there that day.

On the day of last lesson of french in the school of one of the france's district the last banches who were usually empty were occupied by the villagers- former postmaster, former mayor and several other villagers because they want to show their gratitude towards mr. M. Hamel their french teacher for his forty years of faithful service.

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the old hauser with his primer, postman, the mayor and the other village people occupied the back benches on the day of the last lesson.
 

they had come there to show gratitude for the work he had done for the last 40 years
 

The villagers were sitting at the back of the class.They were sitting there because even they like the students were regretting about not learning the French language as they will never again be able to learn it again.And also they were paying respect to the teacher who had been teaching French to the people so dedicatedly since the past 40 years.

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on the day of the last lesson of french in school , the last benches that were always empty were occupied by some elderly people like old hauser, the former mayor, the postmaster and several others besides. The villagers had come to the class show respect to the master, who had given 40 yrs of faithfull service to the school. By these they the villagers were showing their respect to their mother tongue also.  

The villagers occupied the back benches on the day of the last lesson. The order from Berlin caused major changes in school:- 1> From the next day only German would be taught in the school. 2> New teacher would come to replace M. Hamel. The students & even village elders were stunned to hear the news. They were overpowered by a strong patriotic feeling for their native language, French. Everyone wanted to show respect to M. Hamel who had taught French for the last 40 years. Even Franz grew respect for M. Hamel and he ignored how cranky M. Hamel was.