求翻译：2上坡时出现刹车失灵 ，应适时减入中低挡 ，保持足够的动力驶上坡顶停车 。如需半坡停车 ，应保持前进低挡位 ，拉紧手制动 ，随车人员及时用石块 、垫木等物卡住车轮 。如有后滑现象 ，车尾应朝向山坡或安全一面 ，并打开大灯和紧急信号灯 ，引起前后车辆的注意 。是什么意思？

2 uphill when brakes, should timely reduction in low gear, maintaining sufficient momentum heading uphill parking. If mountain parking is required, should maintain a low forward gear, tightened the hand brake, attendant promptly with rocks and mats of wood stuck wheel. If slip after, rear side toward the hillside or security, and turn on lamps and emergency lights, attract the attention of vehicles before and after.