The so-called foil is to reflect and set off. Reflection is the use of light to reveal the image of an object; foil is the use of other things to set off or contrast the characteristics of an object. The contrast in literary works mainly refers to the latter, and the same is naturally true for poetry. From the perspective of "foil or contrast", there are two types of foil, one is positive foil and the other is reverse foil. Li Bai's "Sleepwalking Tianmu Yin Farewell" is a perfect contrast. Just imagine that if you climb halfway up Tianmu Mountain, you can see the sunrise over the East China Sea and hear the crow of roosters. Then the peaks of Tianmu Mountain must reach into the sky and connect to the fairyland, creating the grand scene of "the immortals are lined up like hemp". It makes sense. Another example is "The rooftop is 18,000 feet long, and it is about to fall to the southeast." This describes the height of Tiantai Mountain, but facing Tianmu Mountain, it seems to be falling toward the southeast, which shows that "Tianmu reaches the sky and reaches the sky." A famous example of contrast is Wang Ji's poem "The noisy cicada forest becomes quieter, and the bird singing mountain becomes more secluded". Because the chirping of cicadas sounds so noisy and the chirping of birds sounds so clear, the mountains and forests are extremely quiet. Another example is Du Fu's famous line, "The Zhumen smell of wine and meat, and there are bones frozen to death on the road." The use of "wine and meat smells" to contrast the "bones frozen to death" makes the people's pain and misery even more obvious. The purpose of contrast (whether it is positive or negative) is to highlight the characteristics of the thing being described, or to emphasize the thoughts and emotions to be expressed. There are colors to set off (set off, set off): such as "a little red among the green bushes", the "red" is particularly bright and intense; "the dark clouds are crushing the city, and the light of armor opens towards the golden scales of the sun", "bright" It's extremely eye-catching. Scenery to set off the mood: There are two ways to set off the mood, the decaying scene to set off the sadness, the beautiful scene to set off the joy is the positive setback, such as "I am too drunk to say goodbye, the vast river is soaked in the moon when we say goodbye", "Maple leaves and flowers are rustling in autumn", such as "Two An oriole sings in the green willows, and a row of egrets ascends to the blue sky." The music scene is a contrast to the sadness (or on the contrary), such as Du Fu's poem "The blue birds on the river are more white, and the green flowers on the mountains are about to burn. When is the return year? "Some characters contrast with each other: "The plower forgets his plow, the hoeer forgets his hoe. When he comes back, he is angry with each other, but he sits and watches Luofu" ("Mo Shang Sang"), which expresses the beauty of Luofu; "it is inevitable to be praised by others. A girl's smile only makes the emperor temporarily covered in dust" (Li Shangyin's "Huaqing Palace"), which satirizes Concubine Yang's beauty and her beauty. There is a contrast between movement and stillness: "The bright moon shines among the pines, and the clear spring flows up the rocks"; "No one can be seen in the empty mountain, but the sound of people's voices can be heard"; "Everything is silent here, except for the sound of bells and chimes"; "The carriages and horses have been silent for four thousand years" , The cicadas are sad at dusk in the deep alleys of ancient locust trees" (Zhang's "East Tower of Faxiong Temple"). In addition, there are also contrasts in terms of size, quantity, temperature, distance, height, light and darkness, etc. You should also pay attention to it when reading and appreciating. To set off means to put something together with other things to set off or contrast it in order to make the characteristics of something stand out. It can also be a comparison between opposite things.
In fact, you only need to remember this. Contrast = foil = positive foil (contrast) + contrast (contrast)
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