Original sentence: The September 11, 2001 attacks (also referred to as 9/11) were a series of coordinated suicide attacks upon the United States of America carried out on Tuesday, September 11, 2001, in which hijackers took control of four U
Edited sentence: The September 11, 2001 attacks (also referred to as 9/11), the worst and most infamous act of terrorism in World history, were a series of coordinated suicide attacks upon the United States of America carried out on Tuesday, September 11, 2001, in which hijackers took control of four U