How does Yu Guangzhong's homesickness reflect the poet's thoughts and feelings? What are the historical reasons for the poet's feelings? Answer with historical knowledge (quickly)

This poem by Yu Guangzhong closely links the mainland of China with Taiwan Province Bay, expressing the author's strong homesickness and unforgettable feelings for the mainland, hometown and relatives.

Historical reasons:

1937 War of Resistance against Japanese Aggression outbreak.

After 1949, Taiwan Province Province was separated from Chinese mainland.