求翻译：1.根据路况和车速控制好方向 ，脱开高速挡 ，同时迅速轰一脚空油 ，将高速挡换入低速挡 。这样 ，发动机会有很大的牵引阻力使车速迅速降低 。另外 ，在换低速挡的同时 ，应结合使用手刹 ，但要注意手刹不能拉紧不放 ，也不能拉得太慢 。如果拉得太紧 ，容易使制动盘“抱死” ，很可能损坏传动机件而丧失制动能力；如果拉得太慢 ，会使制动盘磨损烧蚀而失去制动作用 。是什么意思？

1. under the direction of traffic and speed control, off top gear, while rapid detonation of a foot air-oil, top gear swap in low gear. This engine will have a great deal of traction resistance speed reduced rapidly. In addition, while in low gear change, should use a combination of hand brake, but note that Handbrake cannot be tightened down, nor too slowly. If you pull too tight, easily brake disc "lock" is likely to damage the transmission parts and the loss of braking ability; if you pull too slowly, ablation causes the brake disc wear and loss of brake function.