Original sentence: It changes from plain agricultural fields in the north, to dry, arid hills (an offshoot of the Aravalli Hills of Rajasthan) in the south.Their used to be large natural lakes in the southern part of the city, but most of them have dried up due to mining
Edited sentence: It changes from plain agricultural fields in the north to dry, arid hills (an offshoot of the Aravalli Hills of Rajasthan) in the south.There used to be large natural lakes in the southern part of the city, but most of them have dried up due to mining