What kind of thoughts and feelings does Guithough Shou express?

Guinian Shou is a four-character Yuefu poem written by Cao Cao in the Eastern Han Dynasty, and it is the last chapter of four chapters of Cao Cao's Out of Xiamen. This poem combines philosophical thinking, impassioned and artistic image, and shows the poet's attitude towards life and his ambition to cherish time and make a difference. The original poem wrote: Although the tortoise has a long life, there is still a time. A poisonous snake flew in the fog and was finally covered with dust. An old horse crouches, aiming at a thousand miles. The martyrs were full of courage in their later years. The surplus and contraction period is not only in the sky; Blessings that nourish grace can last forever. I am glad to use this poem to express my inner desire.