营巢

例句：

1. 1. The bird is busy buildingits nest in the tree.
   这只鸟正在忙着在树上筑巢。
2. 2. She decidedto build a new housefor her family.
   她决定为家人建一座新房子。
3. 3. The babysquirrel was busy building itsfirst nest.
   小松鼠忙着建造它的第一个巢穴。