cottonwood/ˈkɑː.t̬ən.wʊd/名词(北美)棉白杨,三角叶杨The cottonwood trees were shedding their fluffy white seeds, blanketing the ground in a snowy layer of cotton-like fibers.这棵杨树正在飘落它们的白色絮絮种子,覆盖在地面上形成一层像棉花般的雪白细纤维。想跟读,去练习