To take an extreme example, farmlands dominated by a single crop are so unstable that one year of bad weather or the invasion of a single pest can destroy the entire crop.

举个极端的例子，以单一作物为主的农田是如此不稳定，一年的坏天气或单一害虫的入侵可以摧毁整个作物。

youdao

Pasture is the most important single crop in British agriculture.

在英国农业中，牧草是最重要的一种作物。

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But experts asid no single crop will revolutionize farming in Africa. Because farmers there grow a mixture of different crops.

但是专家表示没有一种单一的农作物可以给非洲农业带来根本性的变化，因为那里的农民混合种植不同的农作物。

youdao

The reason for that is, if you are just engaged in a single crop farming, well you plant it, you take care of it, and then when the times comes you reap it.

其中的原因是,如果只是种庄稼,你先播种,接着你好生照料它们,然后成熟时收割它们

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That's nearly half the population, who must be resettled before the winter rainy season if they are to plant the single annual rice crop.

CNN: ASIANOW - TIME Asia | East Timor: Step Forward, With Caution

That bottom-dwelling, budget tier, first announced at this past Mobile World Congress, has already seen a couple of category cousins come out into the open (see: Vodafone's G 300 and T-Mobile's G 312), so color us unsurprised to find yet another single-core, Googlefied device crop up at the FCC.

ENGADGET: Huawei Ascend G 302D goes public in FCC docs Mobile