Construction of the Roman Colosseum, which was officially known as the Flavian Amphitheater, began in A.D. 691 during the reign of Vespasian, was completed a decade later, during the reign of Titus, who opened the Colosseum with a one-hundred-day cycle of religious pageants, gladiatorial games, and spectacles.
(A)which was officially known as the Flavian Amphitheater, began in A.D. 69, during the reign of Vespasian,
(B)officially known as the Flavian Amphitheater, begun in A.D. 69, during the reign of Vespasian, and
(C)which was officially known as the Flavian Amphitheater, began in A.D, 69, during the reign of Vespasian, and
(D)officially known as the Flavian Amphitheater and begun in A.D. 69, during the reign of Vespasian it
(E) officially known as the Flavian Amphitheater, which was begun in A.D. 69, during the reign of Vespasian, and
题目分析：A began和划线外的was completed不就两个谓语了吗？不行。B就不能用完成时态begun，干掉。C用and把两个动词连着，可以。D又用begun不行，E用was begun，人家的意思是建造这个东西从什么时候就开始了，意思上没有必要用被动啊，杀。
