Complex sentence: Deng Ai later became an Academician (學士) under the local Commandant (都尉) in Xiangcheng (襄城; present-day Xiangcheng County, Xuchang, Henan), but was not successful in his career because he stuttered when he spoke.
Split into simpler sentences: Deng Ai later became an Academician (學士) under the local Commandant (都尉) in Xiangcheng (襄城; present-day Xiangcheng County, Xuchang, Henan). However, he was not too successful in his career because he stuttered when he spoke.