The whole sentence is "when the rain comes after a long drought, you will meet an old friend in another country, and stay in the bridal chamber for one night."
Interpretation of "long drought meets sweet rain": every encounter; Rain: Good rain, timely rain as one wishes. It rained well after a long drought. Describe what you have been longing for and finally got satisfied.
"After a long drought, meeting an old friend, spending the night in the bridal chamber, ranking first", that is, the four great pleasures of life are a yearning for life by simple people, which will remain unchanged for thousands of years. Every event is a happy event that people eagerly expect. The first two items are related to the surprises and expectations of life, while the last two items are the goals to be pursued and the touches to life. The four major tragedies in life refer to the loss of father in youth, spouse in middle age, children in old age and few teachers.
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[Song] Wang Zhu's "Xi": "Long drought meets rain, and old friends meet in other places; On the wedding night, do it for the first time. "
(One is from "The Poetry of a Prodigy"; There are also unofficial history records written by Du Fu. At the beginning of the Ming Dynasty, Jie Jin, a gifted scholar in Jiangxi Province, created the "Four Happy Dolls" according to four happy events in the Four Happy Poems. But did not specify who did it).
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It is better to be clear than to meet old friends in another country. Mo Wen's wedding night, and as the first. (Feng Ming magnum "wake up" volume 20).
Synonym: when you meet an old friend in a foreign country, you get what you want.
Grammar: subject-predicate type; Become an object; Describe the long-awaited joy of finally getting what you want.
Synonym: Long drought meets dew, long drought meets rain.
Baidu Encyclopedia-Long Drought Meets Sweet Rain