Reasons to worry: Santa María's last big blast was one of the four largest volcaniceruptions in the 20th century, registering a VEI magnitude of 6 and leaving a 700-by-1,000 meter craterbehind.

列入关注的理由： 20世纪四次最大规模的火山爆发，圣塔玛里亚就占了一次，记录的火山爆发指数(VEI)为6级，留下了一个直径为700-1000米的火山口。

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In the last century, four Japanese writers produced a total of seven updated versions of the book.

上个世纪，四位日本作家共创作出7个最新的版本。

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Research methods in this article from the perspective of the last century since the 90's, these four areas of research related Commentary.

本文从研究方法的视角，对上世纪90年代以来，这四个领域内的相关研究进行述评。

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It has been an exhilarating run, producing more change in daily life in the last half-century than humanity has known in the combined four thousand years before it.

FORBES: Computing Desire

Mitsubishi Chemical, Japan's largest chemical maker, has earned an operating profit greater than nonoperating expenses and one-time writeoffs only four times in the last quarter-century, figures Toby Williams, head of Asian chemical research at SBC Warburg in Hong Kong.

FORBES: Setting sun