What is the content of Yang Zhenning's poem "Back to Root"?

The ancient poem "Back to the Root": Yesterday, it was a thousand times, and it was high on the nine peaks.

Digging into the symmetry, I was brave enough to soar in the clouds.

The new days in China have changed, so the mission of my hometown is heavy.

I should be a student, Ling Yunzhi.

Three melodies through the ages, following the jokes.

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