登革热流行期间，未曾接触病毒者中的感染率通常为40%至50%，但在最糟的情况下可高达80%至90%。

During epidemics of dengue, infection rates among those who have not been previously exposed to the virus are often between 40% and 50%, but could reach 80% to 90% in worse case scenario.

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每当月亮从我们头顶经过,它的引力就会引起海潮,但那个时候的海潮可与今天的不同,它们高达数百米。

But these weren’t like the tides of today. They were hundreds of meters high.

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世界上碱性最强的环境是碱湖，其pH值可高达12，和氨水相当。

The most alkaline environments in the world are soda lakes, which can have a pH as high as 12, akin to ammonia.

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