《宋史·列传·卷六十一》
余靖主要节制西路，如果叛军向东进犯，那么余靖就不能统辖，无法指挥众将，不如让余靖一人统辖东、西两路。 
又靖专节制西路，若贼东向，则非靖所统，无以使众，不若并付靖经制两路。 从之。
Yu Jing mainly controls the West Road. If the rebels invade from the east, Yu Jing will not be able to command because he cannot command the generals. It is better to let Yu Jing command the East and West Roads alone.
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 又靖专节制西路，若贼东向，则非靖所统，无以使众，不若并付靖经制两路。 从之。 [/INST] Yu Jing mainly controls the West Road. If the rebels invade from the east, Yu Jing will not be able to command because he cannot command the generals. It is better to let Yu Jing command the East and West Roads alone.</s>
Identify the key themes in this Classical Chinese text and explain them in English: 又靖专节制西路，若贼东向，则非靖所统，无以使众，不若并付靖经制两路。 从之。
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Yu Jing mainly controls the West Road. If the rebels invade from the east, Yu Jing will not be able to command because he cannot command the generals. It is better to let Yu Jing command the East and West Roads alone.
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