In Romance, Cao Zhen became a general because his surname was Cao. Cao Zhen's surname is indeed Cao, but "Fu is loyal to his ancestors, and he is not arrogant outside. "Cao Zhen became a general, not by the love of his relatives, but by his own ability.
History: Cao Zun and Zhu Zan died young, and Cao Zhen sympathized with them, "begging for food is a city that honors children". On the other hand, Di Wei's "beauty as an adult gentleman" agreed to his request. When Cao Zhen went to war, the soldiers did not get a reward, so they used their own property as a reward.
Cao Zhen became viceroy mainly because of Sun Quan's meritorious service, which was not mentioned in The Romance. In order to highlight Zhuge Liang and Sima Yi, Zhuge Liang wrote Cao Zhen as an idiot during the Northern Expedition. In fact, the previous wars were mainly led by Cao Zhen. It was not until Cao Zhen's death that Sima Yi, Zhuge Liang's "lifelong enemy", dragged on with Zhuge Liang for four years after Cao Zhen.