以下属于柴油机排放处理机内净化技术的是（）
A.废气再循环系统
B.燃油蒸发控制系统
C.三元催化转换器
D.增压中冷技术
参考答案：D
When a pencil is partly in a glass of water , it looks as if it__________ .
A. breaks B, has broken C. were broken D. had broken
简述疲劳应力的特征
