How does the poet express his feelings in the poem "To a Brother"?

Among Serina Liu's poems, there are three most famous ones: To a Brother. These three poems respectively use apples, pines and phoenixes to describe a loyal and noble figure, which is not only a praise for his younger brother, but also a self-portrayal of the poet. The second is the best, bold and sharp, with the spirit of "standing upright and self-sustaining" and "crossing the secular". In the face of turbulent society, encounter bumps. Therefore, his works are always full of generosity and openness. As he himself said, the more severely persecuted by wind and frost, the more it can reflect the strong and straight nature of pines and cypresses. This spirit and temperament created the elegant and agile style of Serina Liu's poems.