Complex sentence: I hereby request that you commission me as an ambassador to attend Liu Biao's memorial service and console his subordinates, while at the same time, ask Liu Bei to persuade Liu Biao's followers to unite with us to resist Cao Cao.
Split into simpler sentences: I hereby request that you appoint me as your ambassador to attend Liu Biao's memorial service and console his subordinates. At the same time, I'll ask Liu Bei to persuade Liu Biao's followers to unite with us to resist Cao Cao.