There is no snow in the mountains in May, but only cold species. What kind of phenology does ancient poetry and music show?

Song of frontier fortress is the theme of the new Yuefu in Tang Dynasty, and most of the songs are about the life of frontier fortress troops. The author of Li Bai's works is a genius. As a rhythmic poem, he also escaped from Lingyun and created a unique environment. Like this poem, it almost completely breaks through the rhyme. Generally, it is a routine of inheritance and transformation based on couplets. The first four sentences, five or six sentences are inheritance and the last two sentences are transformation, which is completely new. Starting with Snow in Tianshan Mountains, point out "under the plug" and write about the cold in the frontier. May is a hot summer in the mainland, but there is still snow in Tianshan Mountain. But the snow here is not flying snow, but snow. Although there are no snowflakes flying in the air ("no flowers"), I just feel chilly. There are still no flowers in midsummer and May, so you can imagine how cold it is in the remaining dog days (especially in winter). So these two sentences are light and heavy, and the words are vague and ambiguous. At the same time, the word "no flowers" is a pun, but it doesn't mean flowers. This meaning is closely related to three sentences: "flute smells willow" "Zheliu" is the provincial name of Zheliu in Song Dynasty. On the surface, this sentence smells the flute while writing, but in fact there is an implication, which means that there is no willow to fold in front of you, and the matter of "folding willow" can only be heard in the flute. Bright flowers and dark willows are a symbol of spring scenery. "No flowers and no willows", that is, "spring scenery has never been seen". The meaning of these four sentences runs through, "If you are in a straight line, you are not bound" (Shen Deqian's On Poetry). The wording is natural, profound and elegant, and informal, such as the opening of an ancient poem, which is not available to predecessors. Five or six sentences closely carry forward the previous meaning and write the tension of military life. In ancient times, marching sounded golden bells (such as cymbals and bracelets) and drummed quick march. If you don't advance, you will retreat. Writing "golden drums" will set off tension and make military discipline serious. Just saying "Sean Xiao" means marching and fighting all day. I can only take a nap with my saddle in my arms at night, especially the tension of military life. Sleeping on the jade saddle at night may be more in line with the habits of soldiers. It is easy to "hug" without saying "pillow", and the tension is particularly prominent. It seems that once the police are called, people with saddles can turn over and mount their horses and attack bravely. Writing "may" in four sentences makes it almost four o'clock; These two sentences only write a "dawn" and a "night", but they don't describe the whole day's life, and they are also general. The whole article only uses these two sentences as antithesis, which is rigorous in form and suitable for serious content, and enhances the expression effect. The above six sentences are all about the hardships of life in frontier fortress. If there is resentment, the last two sentences suddenly change, and the voice and tone suddenly change. Here is the story of Fu Jiezi in the Western Han Dynasty. Because Loulan Wang (the western domain name) was greedy for money, he sheltered and killed many Chinese envoys to the western regions. Fu Jiezi was sent by Huo Guang to behead King Loulan in the Western Regions to make contributions to the country. The last two sentences of this poem express the patriotic passion of frontier soldiers: "I would like to put my sword under my waist and cut Loulan straight." The words "willing" and "straight" are cut in tone and generous enough to inspire the whole article. This is the crowning touch of a poem. A strong ending is inseparable from the negative contrast of the first six sentences. Without such a hard background, it is not enough to show such outstanding spirit. "Always write the first six sentences for the latter two languages" (Wang Fuzhi), so this poem is extremely desolate and magnificent, and its artistic conception is muddy. Speak boldly when you open your mouth and feel weak. This kind of writing is similar to the sentence "Yellow sand wears golden armor in hundreds of battles, and the broken loulan is not returned". This poem is not only unique in style, but also unconventional in antithesis. "In the body of law, flying to Yao's potential, carrying away strange thoughts" (Yao Nai) is naturally a masterpiece of the Five Laws.