Genetic engineering also may provide a partial solution, as newstrains of drought-resistant crops continue to be developed.
随着抗旱作物新品种的不断开发，基因工程也可能提供部分解决方案。
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Colds mutate even while they're infecting you, and newstrains pop up so often that by the time drug-makers create a vaccine against one variation, the serum is already out of date.