What are the two rhetorical devices used in Homesickness Rhyme?

Yu Guangzhong's poem "Four Rhymes of Homesickness" mainly uses metaphors and rhetorical devices to concretize the abstract homesickness and highlight its depth.

Homesickness is a modern poem written by Yu Guangzhong, a poet, after he returned from a foreign land. Poetry expresses a kind of nostalgia for hometown and motherland. This poem also embodies the poet Yu Guangzhong's good wish for the early reunification of the Chinese nation.

Yu Guangzhong, a famous contemporary writer, poet, scholar and translator, was born in Yongchun, Fujian. Because my mother was originally from Wujin, Jiangsu, she also called herself "Jiangnan". Yu Guangzhong has been engaged in poetry, prose, criticism and translation all his life, calling himself a "four-dimensional space" for his own writing, and is known as a "colorful pen" in the literary world [4]. Galloping in the literary world for more than half a century, he dabbled extensively and was known as "artistic polygamy". His literary career is long and profound, and he is a master of contemporary poetry, an important town of prose, a famous critic and an excellent translator.