valley wall

例句：

1. 1. The valley wall is covered with lush greenery.
   山谷墙覆盖着郁郁葱葱的植被。
2. 2. The valley wall is a popular spot for hiking and picnicking.
   山谷墙是徒步和野餐的热门地点。
3. 3. The valley wall provides a natural barrier against floods.
   山谷墙提供了一个天然的防洪屏障。