Explanation:

Union Government and State Government both can legislate on the subjects written in councurrent list.
The Concurrent List or List-III (Seventh Schedule) is a list of 52 items (though the last item is numbered 47) given in the Seventh Schedule to the Constitution of India.
There is an exception to this in cases "where a law made by the Legislature of a State with respect to one of the matters enumerated in the Concurrent List contains any provision repugnant to the provisions of an earlier law made by Parliament or an existing law with respect to that matter, then, the law so made by the Legislature of such State shall, if it has been reserved for the consideration of the President and has received his assent, prevail in that State.