不是谚语,翻译过来是"好久不见",但其实这是中国式的说法,跟外国人这样说,人家会觉得很费解
参考资料：知识积累||
是成语吧。
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这是中国式英语.不是谚语.但是说英语的人可以理解意思.
这种说法（Chinglish）已经被英语国家所接受。你也会在他们的对话中听见。
下面是摘自www.wikipeida.org，的解释。
Long time no see is often attributed as an example of Chinglish being used by native English speakers. The phrase is said to have originated from 好耐冇見(啦)(Cantonese)/好久不見(了)(Mandarin). These Chinglish phrases were used by dock workers to greet sailors from overseas.
It began in the early 1900s when British and American warships and trading ships often stayed at Chinese docks, and through pidgin communications with dock workers, started to communicate in what is now known as Chinglish. The sailors used the phrase long time no see as a joke when they got home and somehow the phrase became widely used even in English-speaking countries. A more grammatically correct phrase of English should be I haven't seen you for a long time.
While this story is substantiated by other sources [1], this may just be a myth as there are no known records of the origin. The phrase has also been said to originate from trade with American Indians. Similar seemingly grammatically "incorrect" phrases (such as "no pain, no gain" or "the more, the merrier") are common and native to English; thus "long time no see" may have been just a coincidence.
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