loose rock fall

例句：

1. 1. The rock fell from the cliff and crashed into the river below.
   岩石从悬崖上掉落，落入下面的河里。
2. 2. The loose rock could cause a landslide if left unchecked.
   如果放任不管，松散的岩石可能会导致山体滑坡。
3. 3.The loose rock was dangerous to walk on, so we had to wait for it to settle before going further.
   松散的岩石走在上面很危险，所以我们等它稳定了再继续前进。