What role does the first couplet of the poem "Looking Alone in the Border Town" play in the whole poem? Please come in and analyze.

(1)① Point out the topic at the beginning and point out the time and place (1). ② The words "leisurely", "alone" and "full autumn" at the beginning of the poem are shrouded in a lonely and desolate atmosphere (1). (3) The word "desolation of the motherland" in the couplets,

(2) Modify "Twilight Blowing" and "Leng Yun" with "Whispering" and "Sadness", vividly describe the bleak night wind and Leng Yun, and also write the author's mood; "Jing" not only describes the scene of "red leaves" falling in the autumn wind, but also writes the "Jing" in the poet's heart by personification. "Pressure" not only vividly describes Leng Yun's weight, but also shows the poet's heavy mood (just choose two places to appreciate "raining", "misery", "shock" and "pressure", get 1 point for one question correctly, and get 3 points for two questions correctly).