up-hill line

例句：

1. 1. The car was driving upthe hill when it hit a pothole.
   汽车在上坡时撞上了一个坑。
2. 2. The hikers followed the up-hill line to reach the summit.
   登山者沿着上坡线到达山顶。
3. 3. The climbers followed the up-hill line toavoid the steep incline.
   攀岩者沿着上坡线以避免陡峭的斜坡。