sentence: States may not exercise certain powers reserved for the federal government: they may not enter into treaties, alliances or confederations, grant letters of marque or reprisal, coin money or issue bills of credit (such as currency).
modified: fix grammar: States not exercise certain powers reserved for the federal government: they may not enter into treaties, alliances or confederations, grant letters of marque or reprisal, coin money or issue bills of credit (such as currency).