What are the characteristics of what Du Fu wrote and expressed in his poems?

In terms of ideological content, the realistic core of Du Fu's poems is to pay attention to people's sufferings, and the theme is loyalty to the monarch, patriotism and love for the people. (1) Paying attention to people's sufferings is the core content of Du Fu's realistic poems. (2) The Confucian thought of loyalty to the monarch, patriotism and love for the people is the ideological theme of Du Fu's realistic poems. In terms of expression, the artistic feature of Du Fu's realistic poetry creation is to emphasize the expression of real life, and the combination of emotion and freehand brushwork has formed a gloomy and frustrated art.