Original sentence: A crisis concerning who is the legitimate President of Venezuela has been underway since 10 January 2019, when the opposition-majority National Assembly declared that incumbent Nicolás Maduro's 2018 reelection was invalid and the body declared its president, Juan Guaidó, to be acting president of the nation
Edited sentence: A crisis concerning who is the legitimate President of Venezuela has been underway since 10 January 2019, when the opposition-majority National Assembly declared that incumbent Nicolás Maduro's 2018 reelection was invalid and the body elevated its president, Juan Guaidó, as acting president of the nation