What do you mean by an indefinite return date?

0 1 Jun asked about the date of return, from the poem "A rainy night to a friend in the north" written by Li Shangyin, a poet in the late Tang Dynasty. It means that when you ask about the date of return, it's hard to say clearly.

"Short Message to Friends in the North on a Rainy Night" is a lyric quatrain written by Li Shangyin to Chang 'an's wife (or friend) and a poet's reply to each other. Li Shangyin was one of the few poets who deliberately pursued the beauty of poetry in the late Tang Dynasty and even the whole Tang Dynasty. He is good at poetry writing, and parallel prose also has high literary value. His poems are novel in conception and beautiful in style, especially some love poems and untitled poems are touching, beautiful and moving, and are widely read.

A note to a friend in the north on a rainy night: When you ask about your return, the rain will rise to the autumn pool in the evening. When * * * cut the candle at the west window, but talk about the rain at night.

You asked me when I would go back, but I haven't set a date yet. At the moment, evening rain is falling, and the autumn rain is full of Hechi. When can I go back to my hometown, and we can talk while cutting candles under the west window? Then I'll be a guest in Bashan tonight and listen to the drizzle and tell you how lonely I am and how much I miss you!

The first two sentences of this poem, with questions and answers and descriptions of the immediate environment, illustrate the lonely feelings and deep nostalgia for his wife. The last two sentences imagine the joy of meeting again in the future and compare with the loneliness tonight. This poem is improvised, showing the twists and turns of the poet's feelings in an instant.