This poem expresses the poet's feelings about the passage of time. He realized that the long river of history had passed, but he still stayed in this world. The poet experienced many wars and storms, but he didn't stop learning because of it. On the contrary, he returned to study with a firmer belief and pursued the profoundness of knowledge.
This sentence pinned the poet's respect for history and pursuit of knowledge, showing the poet's unswerving spirit of studying and open-minded mind.
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