deep-litter nest

例句：

1. 1.The bird nestled into the tree for warmth.
   这只鸟蜷缩在树上取暖。
2. 2.The scientists found a deep-litter nest in the forest.
   科学家在森林里发现了一个深埋的巢穴。
3. 3.The old man built his deep-litter nest every winter.
   这位老人每年冬天都会建造他的深埋巢穴。