英语语法分析

Paradoxically, Africa's food problems are often ascribed to an overemphasis on nonfood drops.

荒谬的是，非洲的粮食问题往往归咎于过分重视非粮食作物。

But he says nations have to balance the production of biofuel from food crops with biofuel from nonfood resources.

但是他说，国家必需平衡粮食制成和非粮食制成的生物燃料的产量。

At each stage, researchers observed their brain activity using functional MRIs when they were shown food and nonfood items.

研究人员利用功能性核磁共振成像技术(MRI)，观察患者在各个阶段看到食物与非食物时的脑部活动。