em quad

例句：

1. 1.The new car has an em quad system that makes it more efficient on the road.
   这款新车配备了四轮驱动系统，使其在道路上更加高效。
2. 2. The construction crew used an em quad to move heavy equipment across the river.
   施工队使用四轮驱动将重型设备从河这边运到那边。
3. 3.The em quad is a crucial component of the vehicle's suspension system.
   四轮驱动系统是车辆悬挂系统的关键组成部分。