Language, and its translation has more to do with culture than most people believe. In any given country, culture or language, there are gradations of meaning which use different words. Understanding a literally translated sign is hard, especially when the original uses a different alphabet or character set.
For a casual observer who happens to be a non-native speaker, there is no way to translate from the original. Chinese is a tonal language, and this may cause problems during translation, though it does seem that the translator was in the right direction. Without any knowledge of the original language, you would have to take the translation at face value, and add some cultural influences. In this case, the politeness of the culture shows through. The guest is admonished, not warned nor alerted, to please refrain from making confusing noises, while chanting is ongoing.
The politeness to strangers is inherent in most of Asia, especially where the countries still have large agricultural populations, or where the origins of the nation’s people are nomadic. Aside from not knowing the original, the Western guest can only guess at the clues from the translation.
It is possible that the sign is outside of a temple or a church, where hymns are chanted, in which case, the sign is the equivalent of “Church Service ongoing. Please be quiet.” Instead of “Church service” it could be a concert, or a place where music is commonly heard. In the same manner, the admonishment to be quiet, can also be “Silence please.”
During translations, there is also the point where the message is interpreted. In most instances, the message is more important, however, native speakers use a tone and style to convey more meaning and gravity to the words and meaning. This is one instance where the brevity of the translation would be as much welcome or may even be more than the flowery language of the original.
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