The largest, oldest trees would progressively die off and tend not to be replaced.

最大、最老的树会逐渐死去，并且往往不会被取代。

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As a day-to-day essential, it will die off with the generation who read print newspapers.

作为一种日常必需品，它将随着阅读纸质报纸的一代人而消亡。

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Why did the fishes in the pond die off?

为什么池塘里的鱼都死了？

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The die-off was least severe in the southern bay, where there was a 7 percent overall decrease and where new beds were found in the main stem of the James River.

WSJ: Chesapeake Bay grasses decline again

Without new conservation measures, there could be a massive die-off of Caribbean frogs within 15 years, warned Adrell Nunez, an amphibian expert with the Santo Domingo Zoo in the Dominican Republic.

NPR: Alarm Over Vanishing Frogs In The Caribbean

And four other great die-offs have been identified - one of them killing off something like 90% of species.

BBC: Why such a fuss about extinction?