Elaborate the French society structure in …

Clergy belonged to the first estate of that time French society. Clergy were the group of persons who were involved in the special functions in the church like fathers and other members of the church. Nobility belonged to the second estate of the late 18th century French society.
Societal Structure - Ancien Regime

First estate - Clergy (the body of all people who performed religious duties in the Christian Church)
0.5% of the Population.
Was exempt from paying taxes to the State.
Owned a lot of land. 
Collected taxes from the Third Estate called Tithes.

Second Estate - Nobility (aristocracy and feudal lords) 
1.5% of the Population 
Hereditary positions, name carries forward. 
Exempt from paying taxes to the State
Owns a lot of land. 
Collects feudal dues from the peasants working on his lands. 
Peasants obligated to serve the nobility and work in their houses, fields or in their armies.

Third Estate - Commoners 
98% of the Population 
Composed of both rich and poor people. 
Rich - Big businessmen, lawyers, merchants, court officials, lawyers,etc. Also some artisans and free peasants.
Poor - Small peasants, landless labourers, servants, etc. 
They are the ONLY ones who pay direct taxes called Taille as well as indirect taxes to the State. They also pay dues to the clergy and their feudal lords. 

Each estate has only one vote in the Estates General. Moreover, nobility and clergy wield considerable power and influence over the government.