求翻译：4.车辆在下长坡 、陡坡时不管有无情况都应该踩一下刹车 。既可以检验刹车性能 ，也可以在发现刹车失灵时赢得控制车速的时间 ，也称为预见性刹车。是什么意思？

4. vehicle down a long slope, steep grade regardless of whether there should be stepping on the brakes. Either test the brake performance, can also be found when the brakes to win control of speed, also known as predictive brake.