What descriptive techniques are used in Mr. Wen Yiduo's narrative in this article? And briefly talk about its role.

There are many specific descriptions of Wen Yiduo's language and portrait in this paper. For example, bright eyes, messy hair, chin held high, and long flowing beard. There are also detailed descriptions, such as "one big square bamboo paper notebook after another, full of small characters, such as a group of ants waiting in line." All these can play a concrete role in reappearing Mr. Wen Yiduo's respectable tall image, making his spirit, personality and style seem to be something that can be perceived concretely.