Complex sentence: After independence it was taken as one of the five subdivision of Bilaspur, at that time Korba was formed as sub-tehsil, thereafter in 1980 Korba separated from Katghora to form a separate tehsil.
Split into simpler sentences: After independence it was taken as one of the five subdivision of Bilaspur. At that time Korba was formed as sub-tehsil, and thereafter in 1980 Korba separated from Katghora to form a separate tehsil.