As an almost mythical figure, he trusted the wrong person, and his bad luck and his age when he was growing up limited his development.
He carried out his belief, even if he didn't succeed, he was a great strategist and politician, even if he was an indifferent person.
It is unfair to evaluate Zhuge Liang from the perspective of this era. Times are different and ideas are different. In the eyes of modern people, the heroes of that year may be blind and loyal. After so long, our understanding of Zhuge Liang comes from the storytelling of the Three Kingdoms and from TV, and The Romance of the Three Kingdoms itself is an artistically processed novel, and the latter is processed from here, so it is impossible to evaluate who is the real Mr. Wolong.
As long as you see the teacher setting an example, you can understand the first two sentences.