A. 增加农药化肥使用 B. 扩大粮食种植面积 C. 提高单位面积产量 D. 推广转基因作物
A. 正确 B. 错误
A. 较大 B. 一般D3类 C. 一般B3类 D. 重大
A. dirt will cause corrosion of bearing B. bearings will leak oil excessively C. dirt is very abrasive when mixed with grease D. grease will become inflammable