On the creative characteristics of frontier poems in Tang Dynasty, it should be original, thank you.

Features 1. Mainly to grasp the image in the poem. For example: mountains, letters from home, Qiang flute, sunset and so on. 2. Express the poet's feelings. Generally, there are homesickness, patriotism, expressing gratitude, praising the country and so on. 3. Environmental characteristics. Decorate with words such as vastness, desolation, sadness and emptiness. I don't know much about the rise and development, except that it is related to the territorial expansion of the Tang Dynasty. But it depends on the poem and the period. The prosperous Tang Dynasty and the late Tang Dynasty are still very different. Claw machine by hand. Hope to adopt.