Which two poets in ancient China are involved in the following couplets? What's the difference between their poetic styles?

Lao Du, the poet Du Fu; The fallen fairy is the poet Li Bai.

Li Bai and Du Fu are the two peaks of China's Tang poetry and even China's ancient literature. We call them "poetic immortals" and "poetic saints" respectively. Together, they experienced the history of the Tang Dynasty from its heyday to turmoil. In the face of this troubled times, they formed poems with completely different artistic styles and personal personalities.

The style of Li Bai's poems was formed in the most powerful era of the Tang Dynasty, focusing on expressing personal feelings and praising the desire and pursuit of personal value in free life. (History of China Literature) His poems are free and unrestrained, clear and fluent, imaginative and magnificent. He inherited the romantic tradition since The Songs of the South and formed his own unique style.

Du Fu's poetic style was formed in the period of An Shi Rebellion, and gradually took shape in suffering. Du Fu went deep into the society, cared about the sufferings of politics and people's livelihood, and attached importance to realism. He shoulders the heavy responsibility of the country and the nation and faithfully depicts the face of the times and inner feelings. Du Fu's artistic style is gloomy and frustrated.

Li Bai is an outstanding figure of great romanticism, and Du Fu is a great representative of realistic poetry.