Sometimes there are foreshocks, but there is nothing about a foreshock that distinguishes it from any other earthquake, so they're not very useful for prediction.

有时会发生前震，但我们并不能区分前震和其他地震，所以它们对于预测地震并不是很有用。

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The nearest that it has got to predicting a big tremor was in 1983 when a foreshock pointed a finger at a subsequent magnitude 7.7 earthquake within the Sea of Japan.

ECONOMIST: Nature rarely repeats itself | The