填空题 .The Western and Eastern Roman Empires
    At the height of its power, the Roman Empire was so immense that Emperor Diocletian divided the empire into western and eastern halves in 285. The Western Roman Empire was based in Rome while the Eastern Roman Empire later had its capital in Constantinople. Over time, the two empires exhibited distinct methods of rule reflecting their regions. Eventually, the Western Roman Empire fell to barbarian invaders in the late fifth century whereas the Eastern Roman Empire evolved into the Byzantine Empire, which survived for more than 1,000 years before being conquered by the Ottoman Turks in 1453.
    Diocletian opted to divide the empire primarily due to the unwieldiness of ruling a huge amount of territory. By 285, the Roman Empire covered all of Southern Europe and parts of Western Europe, Northern Africa, and the Middle East. Despite having an extensive network of roads and secure shipping lanes, communications were terribly slow. Messages from Rome could take weeks to reach their destinations. Thus provincial governors had a level of autonomy that practically made them minor emperors. A series of conflicts in the decades prior to the split also showed the weakness of far-flung military commands as invasions by border people in the east and west were barely beaten back. In such conditions, local military commanders had to wield absolute power to respond promptly to threats. Such power went to the heads of some of them to the point that generals contemplating usurping the throne were constant threats to the imperial throne. The forming of two empires, each led by a different ruler, was meant to end these problems and to bring stability by giving each emperor more control than a single ruler could wield.
    The reforms accomplished Diocletian's objectives to some degree, but the split also led to great differences between the two halves of the once-united empire. Diocletian had intended for the Eastern ruler to be subordinate to the Western one, but, over time, every emperor ruled as if his empire were separate. This was exacerbated by the differences between the two lands. For instance, despite being a part of the Roman Empire, Greece had dominated the eastern Mediterranean world for centuries. Hence it was natural that the Greek language and Greek customs replaced the Latin language and Roman customs in the Eastern Roman Empire.
    Further problems centered on economic differences between the two halves. The eastern empire was urban based and derived its wealth from trade and work done by artisans. The western empire was more rural and agricultural, and its wealth depended on large populations of people working the land. In time, this weakness led to the decline of the western empire as waves of barbarian invaders devastated the population and land. Diocletian also initiated economic reforms by raising taxes to fund the defense of the empire. In the west, tax collectors had problems getting money from the rural populace, who were spread out, had little currency, and preferred paying taxes in farm produce. In the east, most people lived in cities and had hard currency, so tax collectors had an easier time, making money pour into Constantinople. The end result was a rich, stable Eastern Roman Empire that withstood multiple invasions for a millennium and a poor, unstable Western Roman Empire that succumbed to invasion fewer than two centuries after the split.
    *shipphing lane: a region of water, especially in an ocean or sea, in which numerous ships sail
    *exacerbate: to make worse13.  Vocabulary
    ______=awkwardness