Please illustrate four basic types of modern poetry with examples.

Du Fu's Five-character Rhyme "Spring Hope" is broken, but the mountains and rivers remain forever, and the vegetation turns green in spring. Sad state, can not help but burst into tears, amazing birds, leaving sorrow and hate. The war lasted for more than half a year, and letters from home were rare, with a hundred thousand gold. Twisting with melancholy, scratching my head and thinking, the more I scratch my white hair, I can hardly insert a hairpin.

Li Bai sits alone in Jingting Mountain, birds fly high, and lonely clouds go to leisure alone. You look at me, I look at you, and there are only my eyes and Jingting Mountain's eyes.

Du Fu's seven-character metrical poem reached the peak of "High Wind in the Sky". Apes are sobbing, birds are flying home on clear lakes and white beaches, leaves are falling like the waves of waterfalls, and I watch the long river always roll forward.

I came from three thousand miles away. With the sadness of autumn and my hundred years of sorrow, I climbed this peak alone, and the bad luck formed a layer of frost on my temples. Heartache and fatigue were a thick layer of dust in my wine.

Seven-character quatrains (verses) Li Bai said early in Baidicheng, and Baidicheng bid farewell to colorful clouds. A day later, the apes on both sides of the Taiwan Strait kept crying, and the canoe had passed Chung Shan Man.